xref: /packages/modules/Connectivity/framework/src/android/net/NetworkCapabilities.java

/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.net;

import static com.android.internal.annotations.VisibleForTesting.Visibility.PRIVATE;
import static com.android.net.module.util.BitUtils.appendStringRepresentationOfBitMaskToStringBuilder;
import static com.android.net.module.util.BitUtils.describeDifferences;

import android.annotation.FlaggedApi;
import android.annotation.IntDef;
import android.annotation.LongDef;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.RequiresPermission;
import android.annotation.SuppressLint;
import android.annotation.SystemApi;
import android.compat.annotation.UnsupportedAppUsage;
import android.net.ConnectivityManager.NetworkCallback;
import android.os.Build;
import android.os.Parcel;
import android.os.Parcelable;
import android.os.Process;
import android.text.TextUtils;
import android.util.ArraySet;
import android.util.Log;
import android.util.Range;

import com.android.internal.annotations.VisibleForTesting;
import com.android.modules.utils.build.SdkLevel;
import com.android.net.module.util.BitUtils;
import com.android.net.module.util.CollectionUtils;
import com.android.net.module.util.NetworkCapabilitiesUtils;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import java.util.Set;
import java.util.StringJoiner;

/**
 * Representation of the capabilities of an active network.
 *
 * <p>@see <a href="https://developer.android.com/training/basics/network-ops/reading-network-state>
 * this general guide</a> on how to use NetworkCapabilities and related classes.
 *
 * <p>NetworkCapabilities represent what a network can do and what its
 * characteristics are like. The principal attribute of NetworkCapabilities
 * is in the capabilities bits, which are checked with
 * {@link #hasCapability(int)}. See the list of capabilities and each
 * capability for a description of what it means.
 *
 * <p>Some prime examples include {@code NET_CAPABILITY_MMS}, which means that the
 * network is capable of sending MMS. A network without this capability
 * is not capable of sending MMS.
 * <p>The {@code NET_CAPABILITY_INTERNET} capability means that the network is
 * configured to reach the general Internet. It may or may not actually
 * provide connectivity ; the {@code NET_CAPABILITY_VALIDATED} bit indicates that
 * the system found actual connectivity to the general Internet the last
 * time it checked. Apps interested in actual connectivity should usually
 * look at both these capabilities.
 * <p>The {@code NET_CAPABILITY_NOT_METERED} capability is set for networks that
 * do not bill the user for consumption of bytes. Applications are
 * encouraged to consult this to determine appropriate usage, and to
 * limit usage of metered network where possible, including deferring
 * big downloads until such a time that an unmetered network is connected.
 * Also see {@link android.app.job.JobScheduler} to help with scheduling such
 * downloads, in particular
 * {@link android.app.job.JobInfo.Builder#setRequiredNetwork(NetworkRequest)}.
 * <p>NetworkCapabilities contain a number of other capabilities that
 * represent what modern networks can and can't do. Look up the individual
 * capabilities in this class to learn about each of them.
 *
 * <p>NetworkCapabilities typically represent attributes that can apply to
 * any network. The attributes that apply only to specific transports like
 * cellular or Wi-Fi can be found in the specifier (for requestable attributes)
 * or in the transport info (for non-requestable ones). See
 * {@link #getNetworkSpecifier} and {@link #getTransportInfo}. An app would
 * downcast these to the specific class for the transport they need if they
 * are interested in transport-specific attributes. Also see
 * {@link android.net.wifi.WifiNetworkSpecifier} or
 * {@link android.net.wifi.WifiInfo} for some examples of each of these.
 *
 * <p>NetworkCapabilities also contains other attributes like the estimated
 * upstream and downstream bandwidth and the specific transport of that
 * network (e.g. {@link #TRANSPORT_CELLULAR}). Generally, apps should normally
 * have little reason to check for the type of transport ; for example, to
 * query whether a network costs money to the user, do not look at the
 * transport, but instead look at the absence or presence of
 * {@link #NET_CAPABILITY_NOT_METERED} which will correctly account for
 * metered Wi-Fis and free of charge cell connections.
 *
 * <p>The system communicates with apps about connected networks and uses
 * NetworkCapabilities to express these capabilities about these networks.
 * Apps should register callbacks with the {@link ConnectivityManager#requestNetwork}
 * or {@link ConnectivityManager#registerNetworkCallback} family of methods
 * to learn about the capabilities of a network on a continuous basis
 * and be able to react to changes to capabilities. For quick debugging Android also
 * provides {@link ConnectivityManager#getNetworkCapabilities(Network)},
 * but the dynamic nature of networking makes this ill-suited to production
 * code since capabilities obtained in this way can go stale immediately.
 *
 * <p>Also see {@link NetworkRequest} which uses the same capabilities
 * together with {@link ConnectivityManager#requestNetwork} for how to
 * request the system brings up the kind of network your application needs.
 */
public final class NetworkCapabilities implements Parcelable {
    private static final String TAG = "NetworkCapabilities";

    // TODO : remove this class when udc-mainline-prod is abandoned and android.net.flags.Flags is
    // available here
    /** @hide */
    public static class Flags {
        static final String FLAG_FORBIDDEN_CAPABILITY =
                "com.android.net.flags.forbidden_capability";
        static final String FLAG_NET_CAPABILITY_LOCAL_NETWORK =
                "com.android.net.flags.net_capability_local_network";
        static final String REQUEST_RESTRICTED_WIFI =
                "com.android.net.flags.request_restricted_wifi";
        static final String SUPPORT_TRANSPORT_SATELLITE =
                "com.android.net.flags.support_transport_satellite";
        static final String NET_CAPABILITY_NOT_BANDWIDTH_CONSTRAINED =
                "com.android.net.flags.net_capability_not_bandwidth_constrained";
    }

    /**
     * Mechanism to support redaction of fields in NetworkCapabilities that are guarded by specific
     * app permissions.
     **/
    /**
     * Don't redact any fields since the receiving app holds all the necessary permissions.
     *
     * @hide
     */
    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
    public static final long REDACT_NONE = 0;

    /**
     * Redact any fields that need {@link android.Manifest.permission#ACCESS_FINE_LOCATION}
     * permission since the receiving app does not hold this permission or the location toggle
     * is off.
     *
     * @see android.Manifest.permission#ACCESS_FINE_LOCATION
     * @hide
     */
    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
    public static final long REDACT_FOR_ACCESS_FINE_LOCATION = 1 << 0;

    /**
     * Redact any fields that need {@link android.Manifest.permission#LOCAL_MAC_ADDRESS}
     * permission since the receiving app does not hold this permission.
     *
     * @see android.Manifest.permission#LOCAL_MAC_ADDRESS
     * @hide
     */
    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
    public static final long REDACT_FOR_LOCAL_MAC_ADDRESS = 1 << 1;

    /**
     *
     * Redact any fields that need {@link android.Manifest.permission#NETWORK_SETTINGS}
     * permission since the receiving app does not hold this permission.
     *
     * @see android.Manifest.permission#NETWORK_SETTINGS
     * @hide
     */
    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
    public static final long REDACT_FOR_NETWORK_SETTINGS = 1 << 2;

    /**
     * Redact all fields in this object that require any relevant permission.
     * @hide
     */
    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
    public static final long REDACT_ALL = -1L;

    /** @hide */
    @LongDef(flag = true, prefix = { "REDACT_" }, value = {
            REDACT_NONE,
            REDACT_FOR_ACCESS_FINE_LOCATION,
            REDACT_FOR_LOCAL_MAC_ADDRESS,
            REDACT_FOR_NETWORK_SETTINGS,
            REDACT_ALL
    })
    @Retention(RetentionPolicy.SOURCE)
    public @interface RedactionType {}

    // Set to true when private DNS is broken.
    private boolean mPrivateDnsBroken;

    // Underlying networks, if any. VPNs and VCNs typically have underlying networks.
    // This is an unmodifiable list and it will be returned as is in the getter.
    @Nullable
    private List<Network> mUnderlyingNetworks;

    /**
     * Uid of the app making the request.
     */
    private int mRequestorUid;

    /**
     * Package name of the app making the request.
     */
    private String mRequestorPackageName;

    /**
     * Enterprise capability identifier 1. It will be used to uniquely identify specific
     * enterprise network.
     */
    public static final int NET_ENTERPRISE_ID_1 = 1;

    /**
     * Enterprise capability identifier 2. It will be used to uniquely identify specific
     * enterprise network.
     */
    public static final int NET_ENTERPRISE_ID_2 = 2;

    /**
     * Enterprise capability identifier 3. It will be used to uniquely identify specific
     * enterprise network.
     */
    public static final int NET_ENTERPRISE_ID_3 = 3;

    /**
     * Enterprise capability identifier 4. It will be used to uniquely identify specific
     * enterprise network.
     */
    public static final int NET_ENTERPRISE_ID_4 = 4;

    /**
     * Enterprise capability identifier 5. It will be used to uniquely identify specific
     * enterprise network.
     */
    public static final int NET_ENTERPRISE_ID_5 = 5;

    /** @hide */
    @Retention(RetentionPolicy.SOURCE)
    @IntDef(prefix = { "NET_CAPABILITY_ENTERPRISE_SUB_LEVEL" }, value = {
            NET_ENTERPRISE_ID_1,
            NET_ENTERPRISE_ID_2,
            NET_ENTERPRISE_ID_3,
            NET_ENTERPRISE_ID_4,
            NET_ENTERPRISE_ID_5,
    })
    public @interface EnterpriseId {
    }

    private static final int ALL_VALID_ENTERPRISE_IDS;
    static {
        int enterpriseIds = 0;
        for (int i = NET_ENTERPRISE_ID_1; i <= NET_ENTERPRISE_ID_5; ++i) {
            enterpriseIds |= 1 << i;
        }
        ALL_VALID_ENTERPRISE_IDS = enterpriseIds;
    }

    /**
     * Bitfield representing the network's enterprise capability identifier.  If any are specified
     * they will be satisfied by any Network that matches all of them.
     * See {@link #addEnterpriseId(int)} for details on how masks are added
     */
    private int mEnterpriseId;

    /**
     * Gets the enterprise IDs as an int. Internal callers only.
     *
     * DO NOT USE THIS if not immediately collapsing back into a scalar. Instead,
     * prefer getEnterpriseIds/hasEnterpriseId.
     *
     * @return the internal, version-dependent int representing enterprise ids
     * @hide
     */
    public int getEnterpriseIdsInternal() {
        return mEnterpriseId;
    }

    /**
     * Get enteprise identifiers set.
     *
     * Get all the enterprise capabilities identifier set on this {@code NetworkCapability}
     * If NET_CAPABILITY_ENTERPRISE is set and no enterprise ID is set, it is
     * considered to have NET_CAPABILITY_ENTERPRISE by default.
     * @return all the enterprise capabilities identifier set.
     *
     */
    public @NonNull @EnterpriseId int[] getEnterpriseIds() {
        if (hasCapability(NET_CAPABILITY_ENTERPRISE) && mEnterpriseId == 0) {
            return new int[]{NET_ENTERPRISE_ID_1};
        }
        return BitUtils.unpackBits(mEnterpriseId);
    }

    /**
     * Tests for the presence of an enterprise capability identifier on this instance.
     *
     * If NET_CAPABILITY_ENTERPRISE is set and no enterprise ID is set, it is
     * considered to have NET_CAPABILITY_ENTERPRISE by default.
     * @param enterpriseId the enterprise capability identifier to be tested for.
     * @return {@code true} if set on this instance.
     */
    public boolean hasEnterpriseId(
            @EnterpriseId int enterpriseId) {
        if (enterpriseId == NET_ENTERPRISE_ID_1) {
            if (hasCapability(NET_CAPABILITY_ENTERPRISE) && mEnterpriseId == 0) {
                return true;
            }
        }
        return isValidEnterpriseId(enterpriseId)
                && ((mEnterpriseId & (1L << enterpriseId)) != 0);
    }

    public NetworkCapabilities() {
        clearAll();
        mNetworkCapabilities = DEFAULT_CAPABILITIES;
    }

    public NetworkCapabilities(NetworkCapabilities nc) {
        this(nc, REDACT_NONE);
    }

    /**
     * Make a copy of NetworkCapabilities.
     *
     * @param nc Original NetworkCapabilities
     * @param redactions bitmask of redactions that needs to be performed on this new instance of
     *                   {@link NetworkCapabilities}.
     * @hide
     */
    public NetworkCapabilities(@Nullable NetworkCapabilities nc, @RedactionType long redactions) {
        if (nc != null) {
            set(nc);
        }
        if (mTransportInfo != null) {
            mTransportInfo = nc.mTransportInfo.makeCopy(redactions);
        }
    }

    /**
     * Completely clears the contents of this object, removing even the capabilities that are set
     * by default when the object is constructed.
     * @hide
     */
    public void clearAll() {
        mNetworkCapabilities = mTransportTypes = mForbiddenNetworkCapabilities = 0;
        mLinkUpBandwidthKbps = mLinkDownBandwidthKbps = LINK_BANDWIDTH_UNSPECIFIED;
        mNetworkSpecifier = null;
        mTransportInfo = null;
        mSignalStrength = SIGNAL_STRENGTH_UNSPECIFIED;
        mUids = null;
        mAllowedUids.clear();
        mAdministratorUids = new int[0];
        mOwnerUid = Process.INVALID_UID;
        mSSID = null;
        mPrivateDnsBroken = false;
        mRequestorUid = Process.INVALID_UID;
        mRequestorPackageName = null;
        mSubIds = new ArraySet<>();
        mUnderlyingNetworks = null;
        mEnterpriseId = 0;
    }

    /**
     * Set all contents of this object to the contents of a NetworkCapabilities.
     *
     * @param nc Original NetworkCapabilities
     * @hide
     */
    public void set(@NonNull NetworkCapabilities nc) {
        mNetworkCapabilities = nc.mNetworkCapabilities;
        mTransportTypes = nc.mTransportTypes;
        mLinkUpBandwidthKbps = nc.mLinkUpBandwidthKbps;
        mLinkDownBandwidthKbps = nc.mLinkDownBandwidthKbps;
        mNetworkSpecifier = nc.mNetworkSpecifier;
        if (nc.getTransportInfo() != null) {
            setTransportInfo(nc.getTransportInfo());
        } else {
            setTransportInfo(null);
        }
        mSignalStrength = nc.mSignalStrength;
        mUids = (nc.mUids == null) ? null : new ArraySet<>(nc.mUids);
        setAllowedUids(nc.mAllowedUids);
        setAdministratorUids(nc.getAdministratorUids());
        mOwnerUid = nc.mOwnerUid;
        mForbiddenNetworkCapabilities = nc.mForbiddenNetworkCapabilities;
        mSSID = nc.mSSID;
        mPrivateDnsBroken = nc.mPrivateDnsBroken;
        mRequestorUid = nc.mRequestorUid;
        mRequestorPackageName = nc.mRequestorPackageName;
        mSubIds = new ArraySet<>(nc.mSubIds);
        // mUnderlyingNetworks is an unmodifiable list if non-null, so a defensive copy is not
        // necessary.
        mUnderlyingNetworks = nc.mUnderlyingNetworks;
        mEnterpriseId = nc.mEnterpriseId;
    }

    /**
     * Represents the network's capabilities.  If any are specified they will be satisfied
     * by any Network that matches all of them.
     */
    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
    private long mNetworkCapabilities;

    /**
     * If any capabilities specified here they must not exist in the matching Network.
     */
    private long mForbiddenNetworkCapabilities;

    /** @hide */
    @Retention(RetentionPolicy.SOURCE)
    @IntDef(prefix = { "NET_CAPABILITY_" }, value = {
            NET_CAPABILITY_MMS,
            NET_CAPABILITY_SUPL,
            NET_CAPABILITY_DUN,
            NET_CAPABILITY_FOTA,
            NET_CAPABILITY_IMS,
            NET_CAPABILITY_CBS,
            NET_CAPABILITY_WIFI_P2P,
            NET_CAPABILITY_IA,
            NET_CAPABILITY_RCS,
            NET_CAPABILITY_XCAP,
            NET_CAPABILITY_EIMS,
            NET_CAPABILITY_NOT_METERED,
            NET_CAPABILITY_INTERNET,
            NET_CAPABILITY_NOT_RESTRICTED,
            NET_CAPABILITY_TRUSTED,
            NET_CAPABILITY_NOT_VPN,
            NET_CAPABILITY_VALIDATED,
            NET_CAPABILITY_CAPTIVE_PORTAL,
            NET_CAPABILITY_NOT_ROAMING,
            NET_CAPABILITY_FOREGROUND,
            NET_CAPABILITY_NOT_CONGESTED,
            NET_CAPABILITY_NOT_SUSPENDED,
            NET_CAPABILITY_OEM_PAID,
            NET_CAPABILITY_MCX,
            NET_CAPABILITY_PARTIAL_CONNECTIVITY,
            NET_CAPABILITY_TEMPORARILY_NOT_METERED,
            NET_CAPABILITY_OEM_PRIVATE,
            NET_CAPABILITY_VEHICLE_INTERNAL,
            NET_CAPABILITY_NOT_VCN_MANAGED,
            NET_CAPABILITY_ENTERPRISE,
            NET_CAPABILITY_VSIM,
            NET_CAPABILITY_BIP,
            NET_CAPABILITY_HEAD_UNIT,
            NET_CAPABILITY_MMTEL,
            NET_CAPABILITY_PRIORITIZE_LATENCY,
            NET_CAPABILITY_PRIORITIZE_BANDWIDTH,
            NET_CAPABILITY_LOCAL_NETWORK,
            NET_CAPABILITY_NOT_BANDWIDTH_CONSTRAINED,
    })
    public @interface NetCapability { }

    /**
     * Indicates this is a network that has the ability to reach the
     * carrier's MMSC for sending and receiving MMS messages.
     */
    public static final int NET_CAPABILITY_MMS            = 0;

    /**
     * Indicates this is a network that has the ability to reach the carrier's
     * SUPL server, used to retrieve GPS information.
     */
    public static final int NET_CAPABILITY_SUPL           = 1;

    /**
     * Indicates this is a network that has the ability to reach the carrier's
     * DUN or tethering gateway.
     */
    public static final int NET_CAPABILITY_DUN            = 2;

    /**
     * Indicates this is a network that has the ability to reach the carrier's
     * FOTA portal, used for over the air updates.
     */
    public static final int NET_CAPABILITY_FOTA           = 3;

    /**
     * Indicates this is a network that has the ability to reach the carrier's
     * IMS servers, used for network registration and signaling.
     */
    public static final int NET_CAPABILITY_IMS            = 4;

    /**
     * Indicates this is a network that has the ability to reach the carrier's
     * CBS servers, used for carrier specific services.
     */
    public static final int NET_CAPABILITY_CBS            = 5;

    /**
     * Indicates this is a network that has the ability to reach a Wi-Fi direct
     * peer.
     */
    public static final int NET_CAPABILITY_WIFI_P2P       = 6;

    /**
     * Indicates this is a network that has the ability to reach a carrier's
     * Initial Attach servers.
     */
    public static final int NET_CAPABILITY_IA             = 7;

    /**
     * Indicates this is a network that has the ability to reach a carrier's
     * RCS servers, used for Rich Communication Services.
     */
    public static final int NET_CAPABILITY_RCS            = 8;

    /**
     * Indicates this is a network that has the ability to reach a carrier's
     * XCAP servers, used for configuration and control.
     */
    public static final int NET_CAPABILITY_XCAP           = 9;

    /**
     * Indicates this is a network that has the ability to reach a carrier's
     * Emergency IMS servers or other services, used for network signaling
     * during emergency calls.
     */
    public static final int NET_CAPABILITY_EIMS           = 10;

    /**
     * Indicates that this network is unmetered.
     */
    public static final int NET_CAPABILITY_NOT_METERED    = 11;

    /**
     * Indicates that this network should be able to reach the internet.
     */
    public static final int NET_CAPABILITY_INTERNET       = 12;

    /**
     * Indicates that this network is available for general use.  If this is not set
     * applications should not attempt to communicate on this network.  Note that this
     * is simply informative and not enforcement - enforcement is handled via other means.
     * Set by default.
     */
    public static final int NET_CAPABILITY_NOT_RESTRICTED = 13;

    /**
     * Indicates that the user has indicated implicit trust of this network.  This
     * generally means it's a sim-selected carrier, a plugged in ethernet, a paired
     * BT device or a wifi the user asked to connect to.  Untrusted networks
     * are probably limited to unknown wifi AP.  Set by default.
     */
    public static final int NET_CAPABILITY_TRUSTED        = 14;

    /**
     * Indicates that this network is not a VPN.  This capability is set by default and should be
     * explicitly cleared for VPN networks.
     */
    public static final int NET_CAPABILITY_NOT_VPN        = 15;

    /**
     * Indicates that connectivity on this network was successfully validated. For example, for a
     * network with NET_CAPABILITY_INTERNET, it means that Internet connectivity was successfully
     * detected.
     */
    public static final int NET_CAPABILITY_VALIDATED      = 16;

    /**
     * Indicates that this network was found to have a captive portal in place last time it was
     * probed.
     */
    public static final int NET_CAPABILITY_CAPTIVE_PORTAL = 17;

    /**
     * Indicates that this network is not roaming.
     */
    public static final int NET_CAPABILITY_NOT_ROAMING = 18;

    /**
     * Indicates that this network is available for use by apps, and not a network that is being
     * kept up in the background to facilitate fast network switching.
     */
    public static final int NET_CAPABILITY_FOREGROUND = 19;

    /**
     * Indicates that this network is not congested.
     * <p>
     * When a network is congested, applications should defer network traffic
     * that can be done at a later time, such as uploading analytics.
     */
    public static final int NET_CAPABILITY_NOT_CONGESTED = 20;

    /**
     * Indicates that this network is not currently suspended.
     * <p>
     * When a network is suspended, the network's IP addresses and any connections
     * established on the network remain valid, but the network is temporarily unable
     * to transfer data. This can happen, for example, if a cellular network experiences
     * a temporary loss of signal, such as when driving through a tunnel, etc.
     * A network with this capability is not suspended, so is expected to be able to
     * transfer data.
     */
    public static final int NET_CAPABILITY_NOT_SUSPENDED = 21;

    /**
     * Indicates that traffic that goes through this network is paid by oem. For example,
     * this network can be used by system apps to upload telemetry data.
     * @hide
     */
    @SystemApi
    public static final int NET_CAPABILITY_OEM_PAID = 22;

    /**
     * Indicates this is a network that has the ability to reach a carrier's Mission Critical
     * servers.
     */
    public static final int NET_CAPABILITY_MCX = 23;

    /**
     * Indicates that this network was tested to only provide partial connectivity.
     * @hide
     */
    @SystemApi
    public static final int NET_CAPABILITY_PARTIAL_CONNECTIVITY = 24;

    /**
     * Indicates that this network is temporarily unmetered.
     * <p>
     * This capability will be set for networks that are generally metered, but are currently
     * unmetered, e.g., because the user is in a particular area. This capability can be changed at
     * any time. When it is removed, applications are responsible for stopping any data transfer
     * that should not occur on a metered network.
     * Note that most apps should use {@link #NET_CAPABILITY_NOT_METERED} instead. For more
     * information, see https://developer.android.com/about/versions/11/features/5g#meteredness.
     */
    public static final int NET_CAPABILITY_TEMPORARILY_NOT_METERED = 25;

    /**
     * Indicates that this network is private to the OEM and meant only for OEM use.
     * @hide
     */
    @SystemApi
    public static final int NET_CAPABILITY_OEM_PRIVATE = 26;

    /**
     * Indicates this is an internal vehicle network, meant to communicate with other
     * automotive systems.
     *
     * @hide
     */
    @SystemApi
    public static final int NET_CAPABILITY_VEHICLE_INTERNAL = 27;

    /**
     * Indicates that this network is not subsumed by a Virtual Carrier Network (VCN).
     * <p>
     * To provide an experience on a VCN similar to a single traditional carrier network, in
     * some cases the system sets this bit is set by default in application's network requests,
     * and may choose to remove it at its own discretion when matching the request to a network.
     * <p>
     * Applications that want to know about a Virtual Carrier Network's underlying networks,
     * for example to use them for multipath purposes, should remove this bit from their network
     * requests ; the system will not add it back once removed.
     * @hide
     */
    @SystemApi
    public static final int NET_CAPABILITY_NOT_VCN_MANAGED = 28;

    /**
     * Indicates that this network is intended for enterprise use.
     * <p>
     * 5G URSP rules may indicate that all data should use a connection dedicated for enterprise
     * use. If the enterprise capability is requested, all enterprise traffic will be routed over
     * the connection with this capability.
     */
    public static final int NET_CAPABILITY_ENTERPRISE = 29;

    /**
     * Indicates that this network has ability to access the carrier's Virtual Sim service.
     * @hide
     */
    @SystemApi
    public static final int NET_CAPABILITY_VSIM = 30;

    /**
     * Indicates that this network has ability to support Bearer Independent Protol.
     * @hide
     */
    @SystemApi
    public static final int NET_CAPABILITY_BIP = 31;

    /**
     * Indicates that this network is connected to an automotive head unit.
     */
    public static final int NET_CAPABILITY_HEAD_UNIT = 32;

    /**
     * Indicates that this network has ability to support MMTEL (Multimedia Telephony service).
     */
    public static final int NET_CAPABILITY_MMTEL = 33;

    /**
     * Indicates that this network should be able to prioritize latency for the internet.
     *
     * Starting with {@link Build.VERSION_CODES#UPSIDE_DOWN_CAKE}, requesting this capability with
     * {@link ConnectivityManager#requestNetwork} requires declaration in the self-certified
     * network capabilities. See {@link NetworkRequest} for the self-certification documentation.
     */
    public static final int NET_CAPABILITY_PRIORITIZE_LATENCY = 34;

    /**
     * Indicates that this network should be able to prioritize bandwidth for the internet.
     *
     * Starting with {@link Build.VERSION_CODES#UPSIDE_DOWN_CAKE}, requesting this capability with
     * {@link ConnectivityManager#requestNetwork} requires declaration in the self-certified
     * network capabilities. See {@link NetworkRequest} for the self-certification documentation.
     */
    public static final int NET_CAPABILITY_PRIORITIZE_BANDWIDTH = 35;

    /**
     * Indicates that this network is a local network.
     *
     * Local networks are networks where the device is not obtaining IP addresses from the
     * network, but advertising IP addresses itself. Examples of local networks are:
     * <ul>
     * <li>USB tethering or Wi-Fi hotspot networks to which the device is sharing its Internet
     * connectivity.
     * <li>Thread networks where the current device is the Thread Border Router.
     * <li>Wi-Fi P2P networks where the current device is the Group Owner.
     * </ul>
     *
     * Networks used to obtain Internet access are never local networks.
     *
     * Apps that target an SDK before {@link Build.VERSION_CODES.VANILLA_ICE_CREAM} will not see
     * networks with this capability unless they explicitly set the NET_CAPABILITY_LOCAL_NETWORK
     * in their NetworkRequests.
     */
    @FlaggedApi(Flags.FLAG_NET_CAPABILITY_LOCAL_NETWORK)
    public static final int NET_CAPABILITY_LOCAL_NETWORK = 36;

    /**
     * Indicates that this is not a bandwidth-constrained network.
     *
     * Starting from {@link Build.VERSION_CODES.VANILLA_ICE_CREAM}, this capability is by default
     * set in {@link NetworkRequest}s and true for most networks.
     *
     * If a network lacks this capability, it is bandwidth-constrained. Bandwidth constrained
     * networks cannot support high-bandwidth data transfers and applications that request and use
     * them must ensure that they limit bandwidth usage to below the values returned by
     * {@link #getLinkDownstreamBandwidthKbps()} and {@link #getLinkUpstreamBandwidthKbps()} and
     * limit the frequency of their network usage. If applications perform high-bandwidth data
     * transfers on constrained networks or perform network access too frequently, the system may
     * block the app's access to the network. The system may take other measures to reduce network
     * usage on constrained networks, such as disabling network access to apps that are not in the
     * foreground.
     */
    @FlaggedApi(Flags.NET_CAPABILITY_NOT_BANDWIDTH_CONSTRAINED)
    public static final int NET_CAPABILITY_NOT_BANDWIDTH_CONSTRAINED = 37;

    private static final int MAX_NET_CAPABILITY = NET_CAPABILITY_NOT_BANDWIDTH_CONSTRAINED;

    // Set all bits up to the MAX_NET_CAPABILITY-th bit
    private static final long ALL_VALID_CAPABILITIES = (2L << MAX_NET_CAPABILITY) - 1;

    /**
     * Network capabilities that are expected to be mutable, i.e., can change while a particular
     * network is connected.
     */
    private static final long MUTABLE_CAPABILITIES =
            // TRUSTED can change when user explicitly connects to an untrusted network in Settings.
            // http://b/18206275
            (1L << NET_CAPABILITY_TRUSTED) |
            (1L << NET_CAPABILITY_VALIDATED) |
            (1L << NET_CAPABILITY_CAPTIVE_PORTAL) |
            (1L << NET_CAPABILITY_NOT_ROAMING) |
            (1L << NET_CAPABILITY_FOREGROUND) |
            (1L << NET_CAPABILITY_NOT_CONGESTED) |
            (1L << NET_CAPABILITY_NOT_SUSPENDED) |
            (1L << NET_CAPABILITY_PARTIAL_CONNECTIVITY) |
            (1L << NET_CAPABILITY_TEMPORARILY_NOT_METERED) |
            (1L << NET_CAPABILITY_NOT_VCN_MANAGED) |
            // The value of NET_CAPABILITY_HEAD_UNIT is 32, which cannot use int to do bit shift,
            // otherwise there will be an overflow. Use long to do bit shift instead.
            (1L << NET_CAPABILITY_HEAD_UNIT);

    /**
     * Network capabilities that are not allowed in NetworkRequests. This exists because the
     * NetworkFactory / NetworkAgent model does not deal well with the situation where a
     * capability's presence cannot be known in advance. If such a capability is requested, then we
     * can get into a cycle where the NetworkFactory endlessly churns out NetworkAgents that then
     * get immediately torn down because they do not have the requested capability.
     */
    // Note that as a historical exception, the TRUSTED and NOT_VCN_MANAGED capabilities
    // are mutable but requestable. Factories are responsible for not getting
    // in an infinite loop about these.
    private static final long NON_REQUESTABLE_CAPABILITIES =
            MUTABLE_CAPABILITIES
            & ~(1L << NET_CAPABILITY_TRUSTED)
            & ~(1L << NET_CAPABILITY_NOT_VCN_MANAGED);

    /**
     * Capabilities that are set by default when the object is constructed.
     */
    private static final long DEFAULT_CAPABILITIES;
    static {
        long defaultCapabilities =
                (1L << NET_CAPABILITY_NOT_RESTRICTED)
                | (1L << NET_CAPABILITY_TRUSTED)
                | (1L << NET_CAPABILITY_NOT_VPN);
        if (SdkLevel.isAtLeastV()) {
            defaultCapabilities |= (1L << NET_CAPABILITY_NOT_BANDWIDTH_CONSTRAINED);
        }
        DEFAULT_CAPABILITIES = defaultCapabilities;
    }

    /**
     * Capabilities that are managed by ConnectivityService.
     * @hide
     */
    @VisibleForTesting
    public static final long CONNECTIVITY_MANAGED_CAPABILITIES =
            (1L << NET_CAPABILITY_VALIDATED) |
            (1L << NET_CAPABILITY_CAPTIVE_PORTAL) |
            (1L << NET_CAPABILITY_FOREGROUND) |
            (1L << NET_CAPABILITY_PARTIAL_CONNECTIVITY);

    /**
     * Capabilities that are allowed for all test networks. This list must be set so that it is safe
     * for an unprivileged user to create a network with these capabilities via shell. As such, it
     * must never contain capabilities that are generally useful to the system, such as INTERNET,
     * IMS, SUPL, etc.
     */
    private static final long TEST_NETWORKS_ALLOWED_CAPABILITIES =
            (1L << NET_CAPABILITY_NOT_METERED) |
            (1L << NET_CAPABILITY_TEMPORARILY_NOT_METERED) |
            (1L << NET_CAPABILITY_NOT_RESTRICTED) |
            (1L << NET_CAPABILITY_NOT_VPN) |
            (1L << NET_CAPABILITY_NOT_ROAMING) |
            (1L << NET_CAPABILITY_NOT_CONGESTED) |
            (1L << NET_CAPABILITY_NOT_SUSPENDED) |
            (1L << NET_CAPABILITY_NOT_VCN_MANAGED) |
            (1L << NET_CAPABILITY_NOT_BANDWIDTH_CONSTRAINED);


    /**
     * Extra allowed capabilities for test networks that do not have TRANSPORT_CELLULAR. Test
     * networks with TRANSPORT_CELLULAR must not have those capabilities in order to mitigate
     * the risk of being used by running apps.
     */
    private static final long TEST_NETWORKS_EXTRA_ALLOWED_CAPABILITIES_ON_NON_CELL =
            (1L << NET_CAPABILITY_CBS) |
            (1L << NET_CAPABILITY_DUN) |
            (1L << NET_CAPABILITY_RCS);

    /**
     * Adds the given capability to this {@code NetworkCapability} instance.
     * Note that when searching for a network to satisfy a request, all capabilities
     * requested must be satisfied.
     * <p>
     * If the capability was previously added to the list of forbidden capabilities (either
     * by default or added using {@link #addForbiddenCapability(int)}), then it will be removed
     * from the list of forbidden capabilities as well.
     *
     * @param capability the capability to be added.
     * @return This NetworkCapabilities instance, to facilitate chaining.
     * @hide
     */
    public @NonNull NetworkCapabilities addCapability(@NetCapability int capability) {
        // If the given capability was previously added to the list of forbidden capabilities
        // then the capability will also be removed from the list of forbidden capabilities.
        // TODO: Add forbidden capabilities to the public API
        if (!isValidCapability(capability)) {
            Log.e(TAG, "addCapability is called with invalid capability: " + capability);
            return this;
        }
        mNetworkCapabilities |= 1L << capability;
        // remove from forbidden capability list
        mForbiddenNetworkCapabilities &= ~(1L << capability);
        return this;
    }

    /**
     * Adds the given capability to the list of forbidden capabilities of this
     * {@code NetworkCapability} instance. Note that when searching for a network to
     * satisfy a request, the network must not contain any capability from forbidden capability
     * list.
     * <p>
     * If the capability was previously added to the list of required capabilities (for
     * example, it was there by default or added using {@link #addCapability(int)} method), then
     * it will be removed from the list of required capabilities as well.
     *
     * @see #addCapability(int)
     * @hide
     */
    public void addForbiddenCapability(@NetCapability int capability) {
        if (!isValidCapability(capability)) {
            Log.e(TAG, "addForbiddenCapability is called with invalid capability: " + capability);
            return;
        }
        mForbiddenNetworkCapabilities |= 1L << capability;
        mNetworkCapabilities &= ~(1L << capability);  // remove from requested capabilities
    }

    /**
     * Removes (if found) the given capability from this {@code NetworkCapability}
     * instance that were added via addCapability(int) or setCapabilities(int[], int[]).
     *
     * @param capability the capability to be removed.
     * @return This NetworkCapabilities instance, to facilitate chaining.
     * @hide
     */
    public @NonNull NetworkCapabilities removeCapability(@NetCapability int capability) {
        if (!isValidCapability(capability)) {
            Log.e(TAG, "removeCapability is called with invalid capability: " + capability);
            return this;
        }
        final long mask = ~(1L << capability);
        mNetworkCapabilities &= mask;
        return this;
    }

    /**
     * Removes (if found) the given forbidden capability from this {@link NetworkCapabilities}
     * instance that were added via addForbiddenCapability(int) or setCapabilities(int[], int[]).
     *
     * @param capability the capability to be removed.
     * @return This NetworkCapabilities instance, to facilitate chaining.
     * @hide
     */
    public @NonNull NetworkCapabilities removeForbiddenCapability(@NetCapability int capability) {
        if (!isValidCapability(capability)) {
            Log.e(TAG,
                    "removeForbiddenCapability is called with invalid capability: " + capability);
            return this;
        }
        mForbiddenNetworkCapabilities &= ~(1L << capability);
        return this;
    }

    /**
     * Removes all forbidden capabilities from this {@link NetworkCapabilities} instance.
     * @return This NetworkCapabilities instance, to facilitate chaining.
     * @hide
     */
    public @NonNull NetworkCapabilities removeAllForbiddenCapabilities() {
        mForbiddenNetworkCapabilities = 0;
        return this;
    }

    /**
     * Sets (or clears) the given capability on this {@link NetworkCapabilities}
     * instance.
     * @hide
     */
    public @NonNull NetworkCapabilities setCapability(@NetCapability int capability,
            boolean value) {
        if (value) {
            addCapability(capability);
        } else {
            removeCapability(capability);
        }
        return this;
    }

    /**
     * Gets the capabilities as an int. Internal callers only.
     *
     * DO NOT USE THIS if not immediately collapsing back into a scalar. Instead,
     * prefer getCapabilities/hasCapability.
     *
     * @return an internal, version-dependent int representing the capabilities
     * @hide
     */
    public long getCapabilitiesInternal() {
        return mNetworkCapabilities;
    }

    /**
     * Gets all the capabilities set on this {@code NetworkCapability} instance.
     *
     * @return an array of capability values for this instance.
     */
    public @NonNull @NetCapability int[] getCapabilities() {
        return BitUtils.unpackBits(mNetworkCapabilities);
    }

    /**
     * Gets all the forbidden capabilities set on this {@code NetworkCapability} instance.
     *
     * @return an array of forbidden capability values for this instance.
     * @hide
     */
    @NonNull
    // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public
    public @NetCapability int[] getForbiddenCapabilities() {
        return BitUtils.unpackBits(mForbiddenNetworkCapabilities);
    }


    /**
     * Sets all the capabilities set on this {@code NetworkCapability} instance.
     * This overwrites any existing capabilities.
     *
     * @hide
     */
    public void setCapabilities(@NetCapability int[] capabilities,
            @NetCapability int[] forbiddenCapabilities) {
        mNetworkCapabilities = BitUtils.packBits(capabilities);
        mForbiddenNetworkCapabilities = BitUtils.packBits(forbiddenCapabilities);
    }

    /**
     * @deprecated use {@link #setCapabilities(int[], int[])}
     * @hide
     */
    @Deprecated
    public void setCapabilities(@NetCapability int[] capabilities) {
        setCapabilities(capabilities, new int[] {});
    }

    /**
     * Adds the given enterprise capability identifier to this {@code NetworkCapability} instance.
     * Note that when searching for a network to satisfy a request, all capabilities identifier
     * requested must be satisfied.
     *
     * @param enterpriseId the enterprise capability identifier to be added.
     * @return This NetworkCapabilities instance, to facilitate chaining.
     * @hide
     */
    public @NonNull NetworkCapabilities addEnterpriseId(
            @EnterpriseId int enterpriseId) {
        checkValidEnterpriseId(enterpriseId);
        mEnterpriseId |= 1 << enterpriseId;
        return this;
    }

    /**
     * Removes (if found) the given enterprise capability identifier from this
     * {@code NetworkCapability} instance that were added via addEnterpriseId(int)
     *
     * @param enterpriseId the enterprise capability identifier to be removed.
     * @return This NetworkCapabilities instance, to facilitate chaining.
     * @hide
     */
    private @NonNull NetworkCapabilities removeEnterpriseId(
            @EnterpriseId  int enterpriseId) {
        checkValidEnterpriseId(enterpriseId);
        final int mask = ~(1 << enterpriseId);
        mEnterpriseId &= mask;
        return this;
    }

    /**
     * Set the underlying networks of this network.
     *
     * @param networks The underlying networks of this network.
     *
     * @hide
     */
    public void setUnderlyingNetworks(@Nullable List<Network> networks) {
        mUnderlyingNetworks =
                (networks == null) ? null : Collections.unmodifiableList(new ArrayList<>(networks));
    }

    /**
     * Get the underlying networks of this network. If the caller doesn't have one of
     * {@link android.Manifest.permission.NETWORK_FACTORY},
     * {@link android.Manifest.permission.NETWORK_SETTINGS} and
     * {@link NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK}, this is always redacted to null and
     * it will be never useful to the caller.
     *
     * @return <li>If the list is null, this network hasn't declared underlying networks.</li>
     *         <li>If the list is empty, this network has declared that it has no underlying
     *         networks or it doesn't run on any of the available networks.</li>
     *         <li>The list can contain multiple underlying networks, e.g. a VPN running over
     *         multiple networks at the same time.</li>
     *
     * @hide
     */
    @SuppressLint("NullableCollection")
    @Nullable
    @SystemApi
    public List<Network> getUnderlyingNetworks() {
        return mUnderlyingNetworks;
    }

    private boolean equalsUnderlyingNetworks(@NonNull NetworkCapabilities nc) {
        return Objects.equals(getUnderlyingNetworks(), nc.getUnderlyingNetworks());
    }

    /**
     * Tests for the presence of a capability on this instance.
     *
     * @param capability the capability to be tested for.
     * @return {@code true} if set on this instance.
     */
    public boolean hasCapability(@NetCapability int capability) {
        return isValidCapability(capability)
                && ((mNetworkCapabilities & (1L << capability)) != 0);
    }

    /**
     * Tests for the presence of a forbidden capability on this instance.
     *
     * @param capability the capability to be tested for.
     * @return {@code true} if this capability is set forbidden on this instance.
     * @hide
     */
    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
    // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public
    public boolean hasForbiddenCapability(@NetCapability int capability) {
        return isValidCapability(capability)
                && ((mForbiddenNetworkCapabilities & (1L << capability)) != 0);
    }

    /**
     * Check if this NetworkCapabilities has connectivity-managed capabilities or not.
     * @hide
     */
    public boolean hasConnectivityManagedCapability() {
        return (mNetworkCapabilities & CONNECTIVITY_MANAGED_CAPABILITIES) != 0
                || mForbiddenNetworkCapabilities != 0;
    }

    /**
     * Get the name of the given capability that carriers use.
     * If the capability does not have a carrier-name, returns null.
     *
     * @param capability The capability to get the carrier-name of.
     * @return The carrier-name of the capability, or null if it doesn't exist.
     * @hide
     */
    @SystemApi
    public static @Nullable String getCapabilityCarrierName(@NetCapability int capability) {
        if (capability == NET_CAPABILITY_ENTERPRISE) {
            return capabilityNameOf(capability);
        } else {
            return null;
        }
    }

    /**
     * Convenience function that returns a human-readable description of the first mutable
     * capability we find. Used to present an error message to apps that request mutable
     * capabilities.
     *
     * @hide
     */
    public @Nullable String describeFirstNonRequestableCapability() {
        final long nonRequestable = (mNetworkCapabilities | mForbiddenNetworkCapabilities)
                & NON_REQUESTABLE_CAPABILITIES;

        if (nonRequestable != 0) {
            return capabilityNameOf(BitUtils.unpackBits(nonRequestable)[0]);
        }
        if (mLinkUpBandwidthKbps != 0 || mLinkDownBandwidthKbps != 0) return "link bandwidth";
        if (hasSignalStrength()) return "signalStrength";
        if (isPrivateDnsBroken()) {
            return "privateDnsBroken";
        }
        return null;
    }

    private boolean equalsEnterpriseCapabilitiesId(@NonNull NetworkCapabilities nc) {
        return nc.mEnterpriseId == this.mEnterpriseId;
    }

    private boolean satisfiedByEnterpriseCapabilitiesId(@NonNull NetworkCapabilities nc) {
        final int requestedEnterpriseCapabilitiesId = mEnterpriseId;
        final int providedEnterpriseCapabailitiesId = nc.mEnterpriseId;

        if ((providedEnterpriseCapabailitiesId & requestedEnterpriseCapabilitiesId)
                == requestedEnterpriseCapabilitiesId) {
            return true;
        } else if (providedEnterpriseCapabailitiesId == 0
                && (requestedEnterpriseCapabilitiesId == (1L << NET_ENTERPRISE_ID_1))) {
            return true;
        } else {
            return false;
        }
    }

    private boolean satisfiedByNetCapabilities(@NonNull NetworkCapabilities nc,
            boolean onlyImmutable) {
        long requestedCapabilities = mNetworkCapabilities;
        long requestedForbiddenCapabilities = mForbiddenNetworkCapabilities;
        long providedCapabilities = nc.mNetworkCapabilities;

        if (onlyImmutable) {
            requestedCapabilities &= ~MUTABLE_CAPABILITIES;
            requestedForbiddenCapabilities &= ~MUTABLE_CAPABILITIES;
        }
        return ((providedCapabilities & requestedCapabilities) == requestedCapabilities)
                && ((requestedForbiddenCapabilities & providedCapabilities) == 0);
    }

    /** @hide */
    public boolean equalsNetCapabilities(@NonNull NetworkCapabilities nc) {
        return (nc.mNetworkCapabilities == this.mNetworkCapabilities)
                && (nc.mForbiddenNetworkCapabilities == this.mForbiddenNetworkCapabilities);
    }

    private boolean equalsNetCapabilitiesRequestable(@NonNull NetworkCapabilities that) {
        return ((this.mNetworkCapabilities & ~NON_REQUESTABLE_CAPABILITIES)
                == (that.mNetworkCapabilities & ~NON_REQUESTABLE_CAPABILITIES))
                && ((this.mForbiddenNetworkCapabilities & ~NON_REQUESTABLE_CAPABILITIES)
                == (that.mForbiddenNetworkCapabilities & ~NON_REQUESTABLE_CAPABILITIES));
    }

    /**
     * Removes the NET_CAPABILITY_NOT_RESTRICTED capability if inferring the network is restricted.
     *
     * @hide
     */
    public void maybeMarkCapabilitiesRestricted() {
        if (NetworkCapabilitiesUtils.inferRestrictedCapability(mNetworkCapabilities)) {
            removeCapability(NET_CAPABILITY_NOT_RESTRICTED);
        }
    }

    /**
     * @see #restrictCapabilitiesForTestNetwork(int)
     * @deprecated Use {@link #restrictCapabilitiesForTestNetwork(int)} (without the typo) instead.
     * @hide
     */
    @Deprecated
    public void restrictCapabilitesForTestNetwork(int creatorUid) {
        // Do not remove without careful consideration: this method has a typo in its name but is
        // called by the first S CTS releases, therefore it cannot be removed from the connectivity
        // module as long as such CTS releases are valid for testing S devices.
        restrictCapabilitiesForTestNetwork(creatorUid);
    }

    /**
     * Test networks have strong restrictions on what capabilities they can have. Enforce these
     * restrictions.
     * @hide
     */
    public void restrictCapabilitiesForTestNetwork(int creatorUid) {
        final long originalCapabilities = mNetworkCapabilities;
        final long originalTransportTypes = mTransportTypes;
        final NetworkSpecifier originalSpecifier = mNetworkSpecifier;
        final int originalSignalStrength = mSignalStrength;
        final int originalOwnerUid = getOwnerUid();
        final int[] originalAdministratorUids = getAdministratorUids();
        final TransportInfo originalTransportInfo = getTransportInfo();
        final Set<Integer> originalSubIds = getSubscriptionIds();
        final Set<Integer> originalAllowedUids = new ArraySet<>(mAllowedUids);
        clearAll();
        if (0 != (originalCapabilities & (1 << NET_CAPABILITY_NOT_RESTRICTED))) {
            // If the test network is not restricted, then it is only allowed to declare some
            // specific transports. This is to minimize impact on running apps in case an app
            // run from the shell creates a test a network.
            mTransportTypes =
                    (originalTransportTypes & UNRESTRICTED_TEST_NETWORKS_ALLOWED_TRANSPORTS)
                            | (1 << TRANSPORT_TEST);
        } else {
            // If the test network is restricted, then it may declare any transport.
            mTransportTypes = (originalTransportTypes | (1 << TRANSPORT_TEST));
        }

        if (hasSingleTransport(TRANSPORT_TEST)) {
            // SubIds are only allowed for Test Networks that only declare TRANSPORT_TEST.
            setSubscriptionIds(originalSubIds);
        }

        mNetworkCapabilities = originalCapabilities & TEST_NETWORKS_ALLOWED_CAPABILITIES;
        if (!hasTransport(TRANSPORT_CELLULAR)) {
            mNetworkCapabilities |=
                    (originalCapabilities & TEST_NETWORKS_EXTRA_ALLOWED_CAPABILITIES_ON_NON_CELL);
        }

        mNetworkSpecifier = originalSpecifier;
        mSignalStrength = originalSignalStrength;
        mTransportInfo = originalTransportInfo;
        mAllowedUids.addAll(originalAllowedUids);

        // Only retain the owner and administrator UIDs if they match the app registering the remote
        // caller that registered the network.
        if (originalOwnerUid == creatorUid) {
            setOwnerUid(creatorUid);
        }
        if (CollectionUtils.contains(originalAdministratorUids, creatorUid)) {
            setAdministratorUids(new int[] {creatorUid});
        }
        // There is no need to clear the UIDs, they have already been cleared by clearAll() above.
    }

    /**
     * Representing the transport type.  Apps should generally not care about transport.  A
     * request for a fast internet connection could be satisfied by a number of different
     * transports.  If any are specified here it will be satisfied a Network that matches
     * any of them.  If a caller doesn't care about the transport it should not specify any.
     */
    private long mTransportTypes;

    /** @hide */
    @Retention(RetentionPolicy.SOURCE)
    @IntDef(prefix = { "TRANSPORT_" }, value = {
            TRANSPORT_CELLULAR,
            TRANSPORT_WIFI,
            TRANSPORT_BLUETOOTH,
            TRANSPORT_ETHERNET,
            TRANSPORT_VPN,
            TRANSPORT_WIFI_AWARE,
            TRANSPORT_LOWPAN,
            TRANSPORT_TEST,
            TRANSPORT_USB,
            TRANSPORT_THREAD,
            TRANSPORT_SATELLITE,
    })
    public @interface Transport { }

    /**
     * Indicates this network uses a Cellular transport.
     */
    public static final int TRANSPORT_CELLULAR = 0;

    /**
     * Indicates this network uses a Wi-Fi transport.
     */
    public static final int TRANSPORT_WIFI = 1;

    /**
     * Indicates this network uses a Bluetooth transport.
     */
    public static final int TRANSPORT_BLUETOOTH = 2;

    /**
     * Indicates this network uses an Ethernet transport.
     */
    public static final int TRANSPORT_ETHERNET = 3;

    /**
     * Indicates this network uses a VPN transport.
     */
    public static final int TRANSPORT_VPN = 4;

    /**
     * Indicates this network uses a Wi-Fi Aware transport.
     */
    public static final int TRANSPORT_WIFI_AWARE = 5;

    /**
     * Indicates this network uses a LoWPAN transport.
     */
    public static final int TRANSPORT_LOWPAN = 6;

    /**
     * Indicates this network uses a Test-only virtual interface as a transport.
     *
     * @hide
     */
    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
    public static final int TRANSPORT_TEST = 7;

    /**
     * Indicates this network uses a USB transport.
     */
    public static final int TRANSPORT_USB = 8;

    /**
     * Indicates this network uses a Thread transport.
     */
    public static final int TRANSPORT_THREAD = 9;

    /**
     * Indicates this network uses a Satellite transport.
     */
    @FlaggedApi(Flags.SUPPORT_TRANSPORT_SATELLITE)
    public static final int TRANSPORT_SATELLITE = 10;

    /** @hide */
    public static final int MIN_TRANSPORT = TRANSPORT_CELLULAR;
    /** @hide */
    public static final int MAX_TRANSPORT = TRANSPORT_SATELLITE;

    private static final int ALL_VALID_TRANSPORTS;
    static {
        int transports = 0;
        for (int i = MIN_TRANSPORT; i <= MAX_TRANSPORT; ++i) {
            transports |= 1 << i;
        }
        ALL_VALID_TRANSPORTS = transports;
    }

    /** @hide */
    public static boolean isValidTransport(@Transport int transportType) {
        return (MIN_TRANSPORT <= transportType) && (transportType <= MAX_TRANSPORT);
    }

    private static final String[] TRANSPORT_NAMES = {
        "CELLULAR",
        "WIFI",
        "BLUETOOTH",
        "ETHERNET",
        "VPN",
        "WIFI_AWARE",
        "LOWPAN",
        "TEST",
        "USB",
        "THREAD",
        "SATELLITE",
    };

    /**
     * Allowed transports on an unrestricted test network (in addition to TRANSPORT_TEST).
     */
    private static final long UNRESTRICTED_TEST_NETWORKS_ALLOWED_TRANSPORTS =
            (1L << TRANSPORT_TEST) |
            // Test eth networks are created with EthernetManager#setIncludeTestInterfaces
            (1L << TRANSPORT_ETHERNET) |
            // Test VPN networks can be created but their UID ranges must be empty.
            (1L << TRANSPORT_VPN);

    /**
     * Adds the given transport type to this {@code NetworkCapability} instance.
     * Multiple transports may be applied.  Note that when searching
     * for a network to satisfy a request, any listed in the request will satisfy the request.
     * For example {@code TRANSPORT_WIFI} and {@code TRANSPORT_ETHERNET} added to a
     * {@code NetworkCapabilities} would cause either a Wi-Fi network or an Ethernet network
     * to be selected.  This is logically different than
     * {@code NetworkCapabilities.NET_CAPABILITY_*} listed above.
     *
     * @param transportType the transport type to be added.
     * @return This NetworkCapabilities instance, to facilitate chaining.
     * @hide
     */
    public @NonNull NetworkCapabilities addTransportType(@Transport int transportType) {
        checkValidTransportType(transportType);
        mTransportTypes |= 1 << transportType;
        setNetworkSpecifier(mNetworkSpecifier); // used for exception checking
        return this;
    }

    /**
     * Removes (if found) the given transport from this {@code NetworkCapability} instance.
     *
     * @param transportType the transport type to be removed.
     * @return This NetworkCapabilities instance, to facilitate chaining.
     * @hide
     */
    public @NonNull NetworkCapabilities removeTransportType(@Transport int transportType) {
        checkValidTransportType(transportType);
        mTransportTypes &= ~(1 << transportType);
        setNetworkSpecifier(mNetworkSpecifier); // used for exception checking
        return this;
    }

    /**
     * Sets (or clears) the given transport on this {@link NetworkCapabilities}
     * instance.
     *
     * @hide
     */
    public @NonNull NetworkCapabilities setTransportType(@Transport int transportType,
            boolean value) {
        if (value) {
            addTransportType(transportType);
        } else {
            removeTransportType(transportType);
        }
        return this;
    }

    /**
     * Gets all the transports set on this {@code NetworkCapability} instance.
     *
     * @return an array of transport type values for this instance.
     * @hide
     */
    @SystemApi
    @NonNull public @Transport int[] getTransportTypes() {
        return BitUtils.unpackBits(mTransportTypes);
    }

    /**
     * Gets the transports as an int. Internal callers only.
     *
     * Prefer getTransportTypes/hasTransportType if not immediately collapsing back into a scalar.
     *
     * @return a long integer representing the transport types.
     * @hide
     */
    public long getTransportTypesInternal() {
        return mTransportTypes;
    }

    /**
     * Sets all the transports set on this {@code NetworkCapability} instance.
     * This overwrites any existing transports.
     *
     * @hide
     */
    public void setTransportTypes(@Transport int[] transportTypes) {
        mTransportTypes = BitUtils.packBits(transportTypes);
    }

    /**
     * Tests for the presence of a transport on this instance.
     *
     * @param transportType the transport type to be tested for.
     * @return {@code true} if set on this instance.
     */
    public boolean hasTransport(@Transport int transportType) {
        return isValidTransport(transportType) && ((mTransportTypes & (1 << transportType)) != 0);
    }

    /**
     * Returns true iff this NetworkCapabilities has the specified transport and no other.
     * @hide
     */
    public boolean hasSingleTransport(@Transport int transportType) {
        return mTransportTypes == (1 << transportType);
    }

    /**
     * Returns true iff this NC has the specified transport and no other, ignoring TRANSPORT_TEST.
     *
     * If this NC has the passed transport and no other, this method returns true.
     * If this NC has the passed transport, TRANSPORT_TEST and no other, this method returns true.
     * Otherwise, this method returns false.
     * @hide
     */
    public boolean hasSingleTransportBesidesTest(@Transport int transportType) {
        return (mTransportTypes & ~(1 << TRANSPORT_TEST)) == (1 << transportType);
    }

    private boolean satisfiedByTransportTypes(NetworkCapabilities nc) {
        return ((this.mTransportTypes == 0)
                || ((this.mTransportTypes & nc.mTransportTypes) != 0));
    }

    /** @hide */
    public boolean equalsTransportTypes(NetworkCapabilities nc) {
        return (nc.mTransportTypes == this.mTransportTypes);
    }

    /**
     * UID of the app that owns this network, or Process#INVALID_UID if none/unknown.
     *
     * <p>This field keeps track of the UID of the app that created this network and is in charge of
     * its lifecycle. This could be the UID of apps such as the Wifi network suggestor, the running
     * VPN, or Carrier Service app managing a cellular data connection.
     *
     * <p>For NetworkCapability instances being sent from ConnectivityService, this value MUST be
     * reset to Process.INVALID_UID unless all the following conditions are met:
     *
     * <p>The caller is the network owner, AND one of the following sets of requirements is met:
     *
     * <ol>
     *   <li>The described Network is a VPN
     * </ol>
     *
     * <p>OR:
     *
     * <ol>
     *   <li>The calling app is the network owner
     *   <li>The calling app has the ACCESS_FINE_LOCATION permission granted
     *   <li>The user's location toggle is on
     * </ol>
     *
     * This is because the owner UID is location-sensitive. The apps that request a network could
     * know where the device is if they can tell for sure the system has connected to the network
     * they requested.
     *
     * <p>This is populated by the network agents and for the NetworkCapabilities instance sent by
     * an app to the System Server, the value MUST be reset to Process.INVALID_UID by the system
     * server.
     */
    private int mOwnerUid = Process.INVALID_UID;

    /**
     * Set the UID of the owner app.
     * @hide
     */
    public @NonNull NetworkCapabilities setOwnerUid(final int uid) {
        mOwnerUid = uid;
        return this;
    }

    /**
     * Retrieves the UID of the app that owns this network.
     *
     * <p>For user privacy reasons, this field will only be populated if the following conditions
     * are met:
     *
     * <p>The caller is the network owner, AND one of the following sets of requirements is met:
     *
     * <ol>
     *   <li>The described Network is a VPN
     * </ol>
     *
     * <p>OR:
     *
     * <ol>
     *   <li>The calling app is the network owner
     *   <li>The calling app has the ACCESS_FINE_LOCATION permission granted
     *   <li>The user's location toggle is on
     * </ol>
     *
     * Instances of NetworkCapabilities sent to apps without the appropriate permissions will have
     * this field cleared out.
     *
     * <p>
     * This field will only be populated for VPN and wifi network suggestor apps (i.e using
     * {@link android.net.wifi.WifiNetworkSuggestion WifiNetworkSuggestion}), and only for the
     * network they own. In the case of wifi network suggestors apps, this field is also location
     * sensitive, so the app needs to hold {@link android.Manifest.permission#ACCESS_FINE_LOCATION}
     * permission. If the app targets SDK version greater than or equal to
     * {@link Build.VERSION_CODES#S}, then they also need to use
     * {@link NetworkCallback#FLAG_INCLUDE_LOCATION_INFO} to get the info in their callback. If the
     * apps targets SDK version equal to {{@link Build.VERSION_CODES#R}, this field will always be
     * included. The app will be blamed for location access if this field is included.
     * </p>
     */
    public int getOwnerUid() {
        return mOwnerUid;
    }

    private boolean equalsOwnerUid(@NonNull final NetworkCapabilities nc) {
        return mOwnerUid == nc.mOwnerUid;
    }

    /**
     * UIDs of packages that are administrators of this network, or empty if none.
     *
     * <p>This field tracks the UIDs of packages that have permission to manage this network.
     *
     * <p>Network owners will also be listed as administrators.
     *
     * <p>For NetworkCapability instances being sent from the System Server, this value MUST be
     * empty unless the destination is 1) the System Server, or 2) Telephony. In either case, the
     * receiving entity must have the ACCESS_FINE_LOCATION permission and target R+.
     *
     * <p>When received from an app in a NetworkRequest this is always cleared out by the system
     * server. This field is never used for matching NetworkRequests to NetworkAgents.
     */
    @NonNull private int[] mAdministratorUids = new int[0];

    /**
     * Sets the int[] of UIDs that are administrators of this network.
     *
     * <p>UIDs included in administratorUids gain administrator privileges over this Network.
     * Examples of UIDs that should be included in administratorUids are:
     *
     * <ul>
     *   <li>Carrier apps with privileges for the relevant subscription
     *   <li>Active VPN apps
     *   <li>Other application groups with a particular Network-related role
     * </ul>
     *
     * <p>In general, user-supplied networks (such as WiFi networks) do not have an administrator.
     *
     * <p>An app is granted owner privileges over Networks that it supplies. The owner UID MUST
     * always be included in administratorUids.
     *
     * <p>The administrator UIDs are set by network agents.
     *
     * @param administratorUids the UIDs to be set as administrators of this Network.
     * @throws IllegalArgumentException if duplicate UIDs are contained in administratorUids
     * @see #mAdministratorUids
     * @hide
     */
    @NonNull
    public NetworkCapabilities setAdministratorUids(@NonNull final int[] administratorUids) {
        mAdministratorUids = Arrays.copyOf(administratorUids, administratorUids.length);
        Arrays.sort(mAdministratorUids);
        for (int i = 0; i < mAdministratorUids.length - 1; i++) {
            if (mAdministratorUids[i] >= mAdministratorUids[i + 1]) {
                throw new IllegalArgumentException("All administrator UIDs must be unique");
            }
        }
        return this;
    }

    /**
     * Retrieves the UIDs that are administrators of this Network.
     *
     * <p>This is only populated in NetworkCapabilities objects that come from network agents for
     * networks that are managed by specific apps on the system, such as carrier privileged apps or
     * wifi suggestion apps. This will include the network owner.
     *
     * @return the int[] of UIDs that are administrators of this Network
     * @see #mAdministratorUids
     * @hide
     */
    @NonNull
    @SystemApi
    public int[] getAdministratorUids() {
        return Arrays.copyOf(mAdministratorUids, mAdministratorUids.length);
    }

    /**
     * Tests if the set of administrator UIDs of this network is the same as that of the passed one.
     *
     * <p>The administrator UIDs must be in sorted order.
     *
     * <p>nc is assumed non-null. Else, NPE.
     *
     * @hide
     */
    @VisibleForTesting(visibility = PRIVATE)
    public boolean equalsAdministratorUids(@NonNull final NetworkCapabilities nc) {
        return Arrays.equals(mAdministratorUids, nc.mAdministratorUids);
    }

    /**
     * Value indicating that link bandwidth is unspecified.
     * @hide
     */
    public static final int LINK_BANDWIDTH_UNSPECIFIED = 0;

    /**
     * Passive link bandwidth.  This is a rough guide of the expected peak bandwidth
     * for the first hop on the given transport.  It is not measured, but may take into account
     * link parameters (Radio technology, allocated channels, etc).
     */
    private int mLinkUpBandwidthKbps = LINK_BANDWIDTH_UNSPECIFIED;
    private int mLinkDownBandwidthKbps = LINK_BANDWIDTH_UNSPECIFIED;

    /**
     * Sets the upstream bandwidth for this network in Kbps.  This always only refers to
     * the estimated first hop transport bandwidth.
     * <p>
     * @see Builder#setLinkUpstreamBandwidthKbps
     *
     * @param upKbps the estimated first hop upstream (device to network) bandwidth.
     * @hide
     */
    public @NonNull NetworkCapabilities setLinkUpstreamBandwidthKbps(int upKbps) {
        mLinkUpBandwidthKbps = upKbps;
        return this;
    }

    /**
     * Retrieves the upstream bandwidth for this network in Kbps.  This always only refers to
     * the estimated first hop transport bandwidth.
     *
     * @return The estimated first hop upstream (device to network) bandwidth.
     */
    public int getLinkUpstreamBandwidthKbps() {
        return mLinkUpBandwidthKbps;
    }

    /**
     * Sets the downstream bandwidth for this network in Kbps.  This always only refers to
     * the estimated first hop transport bandwidth.
     * <p>
     * @see Builder#setLinkUpstreamBandwidthKbps
     *
     * @param downKbps the estimated first hop downstream (network to device) bandwidth.
     * @hide
     */
    public @NonNull NetworkCapabilities setLinkDownstreamBandwidthKbps(int downKbps) {
        mLinkDownBandwidthKbps = downKbps;
        return this;
    }

    /**
     * Retrieves the downstream bandwidth for this network in Kbps.  This always only refers to
     * the estimated first hop transport bandwidth.
     *
     * @return The estimated first hop downstream (network to device) bandwidth.
     */
    public int getLinkDownstreamBandwidthKbps() {
        return mLinkDownBandwidthKbps;
    }

    private boolean satisfiedByLinkBandwidths(NetworkCapabilities nc) {
        return !(this.mLinkUpBandwidthKbps > nc.mLinkUpBandwidthKbps
                || this.mLinkDownBandwidthKbps > nc.mLinkDownBandwidthKbps);
    }
    private boolean equalsLinkBandwidths(NetworkCapabilities nc) {
        return (this.mLinkUpBandwidthKbps == nc.mLinkUpBandwidthKbps
                && this.mLinkDownBandwidthKbps == nc.mLinkDownBandwidthKbps);
    }
    /** @hide */
    public static int minBandwidth(int a, int b) {
        if (a == LINK_BANDWIDTH_UNSPECIFIED)  {
            return b;
        } else if (b == LINK_BANDWIDTH_UNSPECIFIED) {
            return a;
        } else {
            return Math.min(a, b);
        }
    }
    /** @hide */
    public static int maxBandwidth(int a, int b) {
        return Math.max(a, b);
    }

    private NetworkSpecifier mNetworkSpecifier = null;
    private TransportInfo mTransportInfo = null;

    /**
     * Sets the optional bearer specific network specifier.
     * This has no meaning if a single transport is also not specified, so calling
     * this without a single transport set will generate an exception, as will
     * subsequently adding or removing transports after this is set.
     * </p>
     *
     * @param networkSpecifier A concrete, parcelable framework class that extends
     *                         NetworkSpecifier.
     * @return This NetworkCapabilities instance, to facilitate chaining.
     * @hide
     */
    public @NonNull NetworkCapabilities setNetworkSpecifier(
            @NonNull NetworkSpecifier networkSpecifier) {
        if (networkSpecifier != null
                // Transport can be test, or test + a single other transport or cellular + satellite
                // transport. Note: cellular + satellite combination is allowed since both transport
                // use the same specifier, TelephonyNetworkSpecifier.
                && mTransportTypes != (1L << TRANSPORT_TEST)
                && Long.bitCount(mTransportTypes & ~(1L << TRANSPORT_TEST)) != 1
                && !specifierAcceptableForMultipleTransports(mTransportTypes)) {
            throw new IllegalStateException("Must have a single non-test transport specified to "
                    + "use setNetworkSpecifier");
        }

        mNetworkSpecifier = networkSpecifier;

        return this;
    }

    private boolean specifierAcceptableForMultipleTransports(long transportTypes) {
        return (transportTypes & ~(1L << TRANSPORT_TEST))
                // Cellular and satellite use the same NetworkSpecifier.
                == (1 << TRANSPORT_CELLULAR | 1 << TRANSPORT_SATELLITE);
    }

    /**
     * Sets the optional transport specific information.
     *
     * @param transportInfo A concrete, parcelable framework class that extends
     * {@link TransportInfo}.
     * @return This NetworkCapabilities instance, to facilitate chaining.
     * @hide
     */
    public @NonNull NetworkCapabilities setTransportInfo(@NonNull TransportInfo transportInfo) {
        mTransportInfo = transportInfo;
        return this;
    }

    /**
     * Gets the optional bearer specific network specifier. May be {@code null} if not set.
     *
     * @return The optional {@link NetworkSpecifier} specifying the bearer specific network
     *         specifier or {@code null}.
     */
    public @Nullable NetworkSpecifier getNetworkSpecifier() {
        return mNetworkSpecifier;
    }

    /**
     * Returns a transport-specific information container. The application may cast this
     * container to a concrete sub-class based on its knowledge of the network request. The
     * application should be able to deal with a {@code null} return value or an invalid case,
     * e.g. use {@code instanceof} operator to verify expected type.
     *
     * @return A concrete implementation of the {@link TransportInfo} class or null if not
     * available for the network.
     */
    @Nullable public TransportInfo getTransportInfo() {
        return mTransportInfo;
    }

    private boolean satisfiedBySpecifier(NetworkCapabilities nc) {
        return mNetworkSpecifier == null || mNetworkSpecifier.canBeSatisfiedBy(nc.mNetworkSpecifier)
                || nc.mNetworkSpecifier instanceof MatchAllNetworkSpecifier;
    }

    private boolean equalsSpecifier(NetworkCapabilities nc) {
        return Objects.equals(mNetworkSpecifier, nc.mNetworkSpecifier);
    }

    private boolean equalsTransportInfo(NetworkCapabilities nc) {
        return Objects.equals(mTransportInfo, nc.mTransportInfo);
    }

    /**
     * Magic value that indicates no signal strength provided. A request specifying this value is
     * always satisfied.
     */
    public static final int SIGNAL_STRENGTH_UNSPECIFIED = Integer.MIN_VALUE;

    /**
     * Signal strength. This is a signed integer, and higher values indicate better signal.
     * The exact units are bearer-dependent. For example, Wi-Fi uses RSSI.
     */
    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P)
    private int mSignalStrength = SIGNAL_STRENGTH_UNSPECIFIED;

    /**
     * Sets the signal strength. This is a signed integer, with higher values indicating a stronger
     * signal. The exact units are bearer-dependent. For example, Wi-Fi uses the same RSSI units
     * reported by wifi code.
     * <p>
     * Note that when used to register a network callback, this specifies the minimum acceptable
     * signal strength. When received as the state of an existing network it specifies the current
     * value. A value of {@link #SIGNAL_STRENGTH_UNSPECIFIED} means no value when received and has
     * no effect when requesting a callback.
     *
     * @param signalStrength the bearer-specific signal strength.
     * @hide
     */
    public @NonNull NetworkCapabilities setSignalStrength(int signalStrength) {
        mSignalStrength = signalStrength;
        return this;
    }

    /**
     * Returns {@code true} if this object specifies a signal strength.
     *
     * @hide
     */
    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
    public boolean hasSignalStrength() {
        return mSignalStrength > SIGNAL_STRENGTH_UNSPECIFIED;
    }

    /**
     * Retrieves the signal strength.
     *
     * @return The bearer-specific signal strength.
     */
    public int getSignalStrength() {
        return mSignalStrength;
    }

    private boolean satisfiedBySignalStrength(NetworkCapabilities nc) {
        return this.mSignalStrength <= nc.mSignalStrength;
    }

    private boolean equalsSignalStrength(NetworkCapabilities nc) {
        return this.mSignalStrength == nc.mSignalStrength;
    }

    /**
     * List of UIDs this network applies to. No restriction if null.
     * <p>
     * For networks, mUids represent the list of network this applies to, and null means this
     * network applies to all UIDs.
     * For requests, mUids is the list of UIDs this network MUST apply to to match ; ALL UIDs
     * must be included in a network so that they match. As an exception to the general rule,
     * a null mUids field for requests mean "no requirements" rather than what the general rule
     * would suggest ("must apply to all UIDs") : this is because this has shown to be what users
     * of this API expect in practice. A network that must match all UIDs can still be
     * expressed with a set ranging the entire set of possible UIDs.
     * <p>
     * mUids is typically (and at this time, only) used by VPN. This network is only available to
     * the UIDs in this list, and it is their default network. Apps in this list that wish to
     * bypass the VPN can do so iff the VPN app allows them to or if they are privileged. If this
     * member is null, then the network is not restricted by app UID. If it's an empty list, then
     * it means nobody can use it.
     * As a special exception, the app managing this network (as identified by its UID stored in
     * mOwnerUid) can always see this network. This is embodied by a special check in
     * satisfiedByUids. That still does not mean the network necessarily <strong>applies</strong>
     * to the app that manages it as determined by #appliesToUid.
     * <p>
     * Please note that in principle a single app can be associated with multiple UIDs because
     * each app will have a different UID when it's run as a different (macro-)user. A single
     * macro user can only have a single active VPN app at any given time however.
     * <p>
     * Also please be aware this class does not try to enforce any normalization on this. Callers
     * can only alter the UIDs by setting them wholesale : this class does not provide any utility
     * to add or remove individual UIDs or ranges. If callers have any normalization needs on
     * their own (like requiring sortedness or no overlap) they need to enforce it
     * themselves. Some of the internal methods also assume this is normalized as in no adjacent
     * or overlapping ranges are present.
     *
     * @hide
     */
    private ArraySet<UidRange> mUids = null;

    /**
     * Convenience method to set the UIDs this network applies to to a single UID.
     * @hide
     */
    public @NonNull NetworkCapabilities setSingleUid(int uid) {
        mUids = new ArraySet<>(1);
        mUids.add(new UidRange(uid, uid));
        return this;
    }

    /**
     * Set the list of UIDs this network applies to.
     * This makes a copy of the set so that callers can't modify it after the call.
     * @hide
     */
    public @NonNull NetworkCapabilities setUids(@Nullable Set<Range<Integer>> uids) {
        mUids = UidRange.fromIntRanges(uids);
        return this;
    }

    /**
     * Get the list of UIDs this network applies to.
     * This returns a copy of the set so that callers can't modify the original object.
     *
     * @return the list of UIDs this network applies to. If {@code null}, then the network applies
     *         to all UIDs.
     * @hide
     */
    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
    @SuppressLint("NullableCollection")
    public @Nullable Set<Range<Integer>> getUids() {
        return UidRange.toIntRanges(mUids);
    }

    /**
     * Get the list of UIDs this network applies to.
     * This returns a copy of the set so that callers can't modify the original object.
     * @hide
     */
    public @Nullable Set<UidRange> getUidRanges() {
        if (mUids == null) return null;

        return new ArraySet<>(mUids);
    }

    /**
     * Test whether this network applies to this UID.
     * @hide
     */
    public boolean appliesToUid(int uid) {
        if (null == mUids) return true;
        for (UidRange range : mUids) {
            if (range.contains(uid)) {
                return true;
            }
        }
        return false;
    }

    /**
     * Tests if the set of UIDs that this network applies to is the same as the passed network.
     * <p>
     * This test only checks whether equal range objects are in both sets. It will
     * return false if the ranges are not exactly the same, even if the covered UIDs
     * are for an equivalent result.
     * <p>
     * Note that this method is not very optimized, which is fine as long as it's not used very
     * often.
     * <p>
     * nc is assumed nonnull, else NPE.
     *
     * @hide
     */
    @VisibleForTesting
    public boolean equalsUids(@NonNull NetworkCapabilities nc) {
        return UidRange.hasSameUids(nc.mUids, mUids);
    }

    /**
     * Test whether the passed NetworkCapabilities satisfies the UIDs this capabilities require.
     *
     * This method is called on the NetworkCapabilities embedded in a request with the
     * capabilities of an available network. It checks whether all the UIDs from this listen
     * (representing the UIDs that must have access to the network) are satisfied by the UIDs
     * in the passed nc (representing the UIDs that this network is available to).
     * <p>
     * As a special exception, the UID that created the passed network (as represented by its
     * mOwnerUid field) always satisfies a NetworkRequest requiring it (of LISTEN
     * or REQUEST types alike), even if the network does not apply to it. That is so a VPN app
     * can see its own network when it listens for it.
     * <p>
     * nc is assumed nonnull. Else, NPE.
     * @see #appliesToUid
     * @hide
     */
    public boolean satisfiedByUids(@NonNull NetworkCapabilities nc) {
        if (null == nc.mUids || null == mUids) return true; // The network satisfies everything.
        for (UidRange requiredRange : mUids) {
            if (requiredRange.contains(nc.mOwnerUid)) return true;
            if (!nc.appliesToUidRange(requiredRange)) {
                return false;
            }
        }
        return true;
    }

    /**
     * Returns whether this network applies to the passed ranges.
     * This assumes that to apply, the passed range has to be entirely contained
     * within one of the ranges this network applies to. If the ranges are not normalized,
     * this method may return false even though all required UIDs are covered because no
     * single range contained them all.
     * @hide
     */
    @VisibleForTesting
    public boolean appliesToUidRange(@NonNull UidRange requiredRange) {
        if (null == mUids) return true;
        for (UidRange uidRange : mUids) {
            if (uidRange.containsRange(requiredRange)) {
                return true;
            }
        }
        return false;
    }

    /**
     * List of UIDs that can always access this network.
     * <p>
     * UIDs in this list have access to this network, even if the network doesn't have the
     * {@link #NET_CAPABILITY_NOT_RESTRICTED} capability and the UID does not hold the
     * {@link android.Manifest.permission.CONNECTIVITY_USE_RESTRICTED_NETWORKS} permission.
     * This is only useful for restricted networks. For non-restricted networks it has no effect.
     * <p>
     * This is disallowed in {@link NetworkRequest}, and can only be set by network agents. Network
     * agents also have restrictions on how they can set these ; they can only back a public
     * Android API. As such, Ethernet agents can set this when backing the per-UID access API, and
     * Telephony can set exactly one UID which has to match the manager app for the associated
     * subscription. Failure to comply with these rules will see this member cleared.
     * <p>
     * This member is never null, but can be empty.
     * @hide
     */
    @NonNull
    private final ArraySet<Integer> mAllowedUids = new ArraySet<>();

    /**
     * Set the list of UIDs that can always access this network.
     * @param uids
     * @hide
     */
    public void setAllowedUids(@NonNull final Set<Integer> uids) {
        // could happen with nc.set(nc), cheaper than always making a defensive copy
        if (uids == mAllowedUids) return;

        Objects.requireNonNull(uids);
        mAllowedUids.clear();
        mAllowedUids.addAll(uids);
    }

    /**
     * The list of UIDs that can always access this network.
     *
     * The UIDs in this list can always access this network, even if it is restricted and
     * the UID doesn't hold the USE_RESTRICTED_NETWORKS permission. This is defined by the
     * network agent in charge of creating the network.
     *
     * The UIDs are only visible to network factories and the system server, since the system
     * server makes sure to redact them before sending a NetworkCapabilities to a process
     * that doesn't hold the permission.
     *
     * @hide
     */
    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
    @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
    public @NonNull Set<Integer> getAllowedUids() {
        return new ArraySet<>(mAllowedUids);
    }

    /** @hide */
    // For internal clients that know what they are doing and need to avoid the performance hit
    // of the defensive copy.
    public @NonNull ArraySet<Integer> getAllowedUidsNoCopy() {
        return mAllowedUids;
    }

    /**
     * Test whether this UID has special permission to access this network, as per mAllowedUids.
     * @hide
     */
    // TODO : should this be "doesUidHaveAccess" and check the USE_RESTRICTED_NETWORKS permission ?
    public boolean isUidWithAccess(int uid) {
        return mAllowedUids.contains(uid);
    }

    /**
     * @return whether any UID is in the list of access UIDs
     * @hide
     */
    public boolean hasAllowedUids() {
        return !mAllowedUids.isEmpty();
    }

    private boolean equalsAllowedUids(@NonNull NetworkCapabilities other) {
        return mAllowedUids.equals(other.mAllowedUids);
    }

    /**
     * The SSID of the network, or null if not applicable or unknown.
     * <p>
     * This is filled in by wifi code.
     * @hide
     */
    private String mSSID;

    /**
     * Sets the SSID of this network.
     * @hide
     */
    public @NonNull NetworkCapabilities setSSID(@Nullable String ssid) {
        mSSID = ssid;
        return this;
    }

    /**
     * Gets the SSID of this network, or null if none or unknown.
     * @hide
     */
    @SystemApi
    public @Nullable String getSsid() {
        return mSSID;
    }

    /**
     * Tests if the SSID of this network is the same as the SSID of the passed network.
     * @hide
     */
    public boolean equalsSSID(@NonNull NetworkCapabilities nc) {
        return Objects.equals(mSSID, nc.mSSID);
    }

    /**
     * Check if the SSID requirements of this object are matched by the passed object.
     * @hide
     */
    public boolean satisfiedBySSID(@NonNull NetworkCapabilities nc) {
        return mSSID == null || mSSID.equals(nc.mSSID);
    }

    /**
     * Check if our requirements are satisfied by the given {@code NetworkCapabilities}.
     *
     * @param nc the {@code NetworkCapabilities} that may or may not satisfy our requirements.
     * @param onlyImmutable if {@code true}, do not consider mutable requirements such as link
     *         bandwidth, signal strength, or validation / captive portal status.
     *
     * @hide
     */
    private boolean satisfiedByNetworkCapabilities(NetworkCapabilities nc, boolean onlyImmutable) {
        return (nc != null
                && satisfiedByNetCapabilities(nc, onlyImmutable)
                && satisfiedByTransportTypes(nc)
                && (onlyImmutable || satisfiedByLinkBandwidths(nc))
                && satisfiedBySpecifier(nc)
                && satisfiedByEnterpriseCapabilitiesId(nc)
                && (onlyImmutable || satisfiedBySignalStrength(nc))
                && (onlyImmutable || satisfiedByUids(nc))
                && (onlyImmutable || satisfiedBySSID(nc))
                && (onlyImmutable || satisfiedByRequestor(nc))
                && (onlyImmutable || satisfiedBySubscriptionIds(nc)));
    }

    /**
     * Check if our requirements are satisfied by the given {@code NetworkCapabilities}.
     *
     * @param nc the {@code NetworkCapabilities} that may or may not satisfy our requirements.
     *
     * @hide
     */
    @SystemApi
    public boolean satisfiedByNetworkCapabilities(@Nullable NetworkCapabilities nc) {
        return satisfiedByNetworkCapabilities(nc, false);
    }

    /**
     * Check if our immutable requirements are satisfied by the given {@code NetworkCapabilities}.
     *
     * @param nc the {@code NetworkCapabilities} that may or may not satisfy our requirements.
     *
     * @hide
     */
    public boolean satisfiedByImmutableNetworkCapabilities(@Nullable NetworkCapabilities nc) {
        return satisfiedByNetworkCapabilities(nc, true);
    }

    /**
     * Checks that our immutable capabilities are the same as those of the given
     * {@code NetworkCapabilities} and return a String describing any difference.
     * The returned String is empty if there is no difference.
     *
     * @hide
     */
    public String describeImmutableDifferences(@Nullable NetworkCapabilities that) {
        if (that == null) {
            return "other NetworkCapabilities was null";
        }

        StringJoiner joiner = new StringJoiner(", ");

        // Ignore NOT_METERED being added or removed as it is effectively dynamic. http://b/63326103
        // TODO: properly support NOT_METERED as a mutable and requestable capability.
        final long mask = ~MUTABLE_CAPABILITIES & ~(1 << NET_CAPABILITY_NOT_METERED);
        long oldImmutableCapabilities = this.mNetworkCapabilities & mask;
        long newImmutableCapabilities = that.mNetworkCapabilities & mask;
        if (oldImmutableCapabilities != newImmutableCapabilities) {
            String before = capabilityNamesOf(BitUtils.unpackBits(
                    oldImmutableCapabilities));
            String after = capabilityNamesOf(BitUtils.unpackBits(
                    newImmutableCapabilities));
            joiner.add(String.format("immutable capabilities changed: %s -> %s", before, after));
        }

        if (!equalsSpecifier(that)) {
            NetworkSpecifier before = this.getNetworkSpecifier();
            NetworkSpecifier after = that.getNetworkSpecifier();
            joiner.add(String.format("specifier changed: %s -> %s", before, after));
        }

        if (!equalsTransportTypes(that)) {
            String before = transportNamesOf(this.getTransportTypes());
            String after = transportNamesOf(that.getTransportTypes());
            joiner.add(String.format("transports changed: %s -> %s", before, after));
        }

        return joiner.toString();
    }

    /**
     * Returns a short but human-readable string of updates from an older set of capabilities.
     * @param old the old capabilities to diff from
     * @return a string fit for logging differences, or null if no differences.
     *         this never returns the empty string. See BitUtils#describeDifferences.
     * @hide
     */
    @Nullable
    public String describeCapsDifferencesFrom(@Nullable final NetworkCapabilities old) {
        final long oldCaps = null == old ? 0 : old.mNetworkCapabilities;
        return describeDifferences(oldCaps, mNetworkCapabilities,
                NetworkCapabilities::capabilityNameOf);
    }

    /**
     * Checks that our requestable capabilities are the same as those of the given
     * {@code NetworkCapabilities}.
     *
     * @hide
     */
    public boolean equalRequestableCapabilities(@Nullable NetworkCapabilities nc) {
        if (nc == null) return false;
        return (equalsNetCapabilitiesRequestable(nc)
                && equalsTransportTypes(nc)
                && equalsSpecifier(nc));
    }

    @Override
    public boolean equals(@Nullable Object obj) {
        if (obj == null || (obj instanceof NetworkCapabilities == false)) return false;
        NetworkCapabilities that = (NetworkCapabilities) obj;
        return equalsNetCapabilities(that)
                && equalsTransportTypes(that)
                && equalsLinkBandwidths(that)
                && equalsSignalStrength(that)
                && equalsSpecifier(that)
                && equalsTransportInfo(that)
                && equalsUids(that)
                && equalsAllowedUids(that)
                && equalsSSID(that)
                && equalsOwnerUid(that)
                && equalsPrivateDnsBroken(that)
                && equalsRequestor(that)
                && equalsAdministratorUids(that)
                && equalsSubscriptionIds(that)
                && equalsUnderlyingNetworks(that)
                && equalsEnterpriseCapabilitiesId(that);
    }

    @Override
    public int hashCode() {
        return (int) (mNetworkCapabilities & 0xFFFFFFFF)
                + ((int) (mNetworkCapabilities >> 32) * 3)
                + ((int) (mForbiddenNetworkCapabilities & 0xFFFFFFFF) * 5)
                + ((int) (mForbiddenNetworkCapabilities >> 32) * 7)
                + ((int) (mTransportTypes & 0xFFFFFFFF) * 11)
                + ((int) (mTransportTypes >> 32) * 13)
                + mLinkUpBandwidthKbps * 17
                + mLinkDownBandwidthKbps * 19
                + Objects.hashCode(mNetworkSpecifier) * 23
                + mSignalStrength * 29
                + mOwnerUid * 31
                + Objects.hashCode(mUids) * 37
                + Objects.hashCode(mAllowedUids) * 41
                + Objects.hashCode(mSSID) * 43
                + Objects.hashCode(mTransportInfo) * 47
                + Objects.hashCode(mPrivateDnsBroken) * 53
                + Objects.hashCode(mRequestorUid) * 59
                + Objects.hashCode(mRequestorPackageName) * 61
                + Arrays.hashCode(mAdministratorUids) * 67
                + Objects.hashCode(mSubIds) * 71
                + Objects.hashCode(mUnderlyingNetworks) * 73
                + mEnterpriseId * 79;
    }

    @Override
    public int describeContents() {
        return 0;
    }

    private <T extends Parcelable> void writeParcelableArraySet(Parcel in,
            @Nullable ArraySet<T> val, int flags) {
        final int size = (val != null) ? val.size() : -1;
        in.writeInt(size);
        for (int i = 0; i < size; i++) {
            in.writeParcelable(val.valueAt(i), flags);
        }
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeLong(mNetworkCapabilities & ALL_VALID_CAPABILITIES);
        dest.writeLong(mForbiddenNetworkCapabilities & ALL_VALID_CAPABILITIES);
        dest.writeLong(mTransportTypes & ALL_VALID_TRANSPORTS);
        dest.writeInt(mLinkUpBandwidthKbps);
        dest.writeInt(mLinkDownBandwidthKbps);
        dest.writeParcelable((Parcelable) mNetworkSpecifier, flags);
        dest.writeParcelable((Parcelable) mTransportInfo, flags);
        dest.writeInt(mSignalStrength);
        writeParcelableArraySet(dest, mUids, flags);
        dest.writeIntArray(CollectionUtils.toIntArray(mAllowedUids));
        dest.writeString(mSSID);
        dest.writeBoolean(mPrivateDnsBroken);
        dest.writeIntArray(getAdministratorUids());
        dest.writeInt(mOwnerUid);
        dest.writeInt(mRequestorUid);
        dest.writeString(mRequestorPackageName);
        dest.writeIntArray(CollectionUtils.toIntArray(mSubIds));
        dest.writeTypedList(mUnderlyingNetworks);
        dest.writeInt(mEnterpriseId & ALL_VALID_ENTERPRISE_IDS);
    }

    public static final @android.annotation.NonNull Creator<NetworkCapabilities> CREATOR =
            new Creator<>() {
            @Override
            public NetworkCapabilities createFromParcel(Parcel in) {
                NetworkCapabilities netCap = new NetworkCapabilities();
                // Validate the unparceled data, in case the parceling party was malicious.
                netCap.mNetworkCapabilities = in.readLong() & ALL_VALID_CAPABILITIES;
                netCap.mForbiddenNetworkCapabilities = in.readLong() & ALL_VALID_CAPABILITIES;
                netCap.mTransportTypes = in.readLong() & ALL_VALID_TRANSPORTS;
                netCap.mLinkUpBandwidthKbps = in.readInt();
                netCap.mLinkDownBandwidthKbps = in.readInt();
                netCap.mNetworkSpecifier = in.readParcelable(null);
                netCap.mTransportInfo = in.readParcelable(null);
                netCap.mSignalStrength = in.readInt();
                netCap.mUids = readParcelableArraySet(in, null /* ClassLoader, null for default */);
                final int[] allowedUids = in.createIntArray();
                netCap.mAllowedUids.ensureCapacity(allowedUids.length);
                for (int uid : allowedUids) {
                    netCap.mAllowedUids.add(uid);
                }
                netCap.mSSID = in.readString();
                netCap.mPrivateDnsBroken = in.readBoolean();
                netCap.setAdministratorUids(in.createIntArray());
                netCap.mOwnerUid = in.readInt();
                netCap.mRequestorUid = in.readInt();
                netCap.mRequestorPackageName = in.readString();
                netCap.mSubIds = new ArraySet<>();
                final int[] subIdInts = Objects.requireNonNull(in.createIntArray());
                for (int i = 0; i < subIdInts.length; i++) {
                    netCap.mSubIds.add(subIdInts[i]);
                }
                netCap.setUnderlyingNetworks(in.createTypedArrayList(Network.CREATOR));
                netCap.mEnterpriseId = in.readInt() & ALL_VALID_ENTERPRISE_IDS;
                return netCap;
            }
            @Override
            public NetworkCapabilities[] newArray(int size) {
                return new NetworkCapabilities[size];
            }

            private @Nullable <T extends Parcelable> ArraySet<T> readParcelableArraySet(Parcel in,
                    @Nullable ClassLoader loader) {
                final int size = in.readInt();
                if (size < 0) {
                    return null;
                }
                final ArraySet<T> result = new ArraySet<>(size);
                for (int i = 0; i < size; i++) {
                    final T value = in.readParcelable(loader);
                    result.add(value);
                }
                return result;
            }
        };

    @Override
    public @NonNull String toString() {
        final StringBuilder sb = new StringBuilder("[");
        if (0 != mTransportTypes) {
            sb.append(" Transports: ");
            appendStringRepresentationOfBitMaskToStringBuilder(sb, mTransportTypes,
                    NetworkCapabilities::transportNameOf, "|");
        }
        if (0 != mNetworkCapabilities) {
            sb.append(" Capabilities: ");
            appendStringRepresentationOfBitMaskToStringBuilder(sb, mNetworkCapabilities,
                    NetworkCapabilities::capabilityNameOf, "&");
        }
        if (0 != mForbiddenNetworkCapabilities) {
            sb.append(" Forbidden: ");
            appendStringRepresentationOfBitMaskToStringBuilder(sb, mForbiddenNetworkCapabilities,
                    NetworkCapabilities::capabilityNameOf, "&");
        }
        if (mLinkUpBandwidthKbps > 0) {
            sb.append(" LinkUpBandwidth>=").append(mLinkUpBandwidthKbps).append("Kbps");
        }
        if (mLinkDownBandwidthKbps > 0) {
            sb.append(" LinkDnBandwidth>=").append(mLinkDownBandwidthKbps).append("Kbps");
        }
        if (mNetworkSpecifier != null) {
            sb.append(" Specifier: <").append(mNetworkSpecifier).append(">");
        }
        if (mTransportInfo != null) {
            sb.append(" TransportInfo: <").append(mTransportInfo).append(">");
        }
        if (hasSignalStrength()) {
            sb.append(" SignalStrength: ").append(mSignalStrength);
        }

        if (null != mUids) {
            if ((1 == mUids.size()) && (mUids.valueAt(0).count() == 1)) {
                sb.append(" Uid: ").append(mUids.valueAt(0).start);
            } else {
                sb.append(" Uids: <").append(mUids).append(">");
            }
        }

        if (hasAllowedUids()) {
            sb.append(" AllowedUids: <").append(mAllowedUids).append(">");
        }

        if (mOwnerUid != Process.INVALID_UID) {
            sb.append(" OwnerUid: ").append(mOwnerUid);
        }

        if (mAdministratorUids != null && mAdministratorUids.length != 0) {
            sb.append(" AdminUids: ").append(Arrays.toString(mAdministratorUids));
        }

        if (mRequestorUid != Process.INVALID_UID) {
            sb.append(" RequestorUid: ").append(mRequestorUid);
        }

        if (mRequestorPackageName != null) {
            sb.append(" RequestorPkg: ").append(mRequestorPackageName);
        }

        if (null != mSSID) {
            sb.append(" SSID: ").append(mSSID);
        }

        if (mPrivateDnsBroken) {
            sb.append(" PrivateDnsBroken");
        }

        if (!mSubIds.isEmpty()) {
            sb.append(" SubscriptionIds: ").append(mSubIds);
        }

        if (0 != mEnterpriseId) {
            sb.append(" EnterpriseId: ");
            appendStringRepresentationOfBitMaskToStringBuilder(sb, mEnterpriseId,
                    NetworkCapabilities::enterpriseIdNameOf, "&");
        }

        sb.append(" UnderlyingNetworks: ");
        if (mUnderlyingNetworks != null) {
            sb.append("[");
            final StringJoiner joiner = new StringJoiner(",");
            for (int i = 0; i < mUnderlyingNetworks.size(); i++) {
                joiner.add(mUnderlyingNetworks.get(i).toString());
            }
            sb.append(joiner.toString());
            sb.append("]");
        } else {
            sb.append("Null");
        }

        sb.append("]");
        return sb.toString();
    }

    /**
     * @hide
     */
    public static @NonNull String capabilityNamesOf(@Nullable @NetCapability int[] capabilities) {
        StringJoiner joiner = new StringJoiner("|");
        if (capabilities != null) {
            for (int c : capabilities) {
                joiner.add(capabilityNameOf(c));
            }
        }
        return joiner.toString();
    }

    /**
     * @hide
     */
    public static @NonNull String capabilityNameOf(@NetCapability int capability) {
        switch (capability) {
            case NET_CAPABILITY_MMS:                  return "MMS";
            case NET_CAPABILITY_SUPL:                 return "SUPL";
            case NET_CAPABILITY_DUN:                  return "DUN";
            case NET_CAPABILITY_FOTA:                 return "FOTA";
            case NET_CAPABILITY_IMS:                  return "IMS";
            case NET_CAPABILITY_CBS:                  return "CBS";
            case NET_CAPABILITY_WIFI_P2P:             return "WIFI_P2P";
            case NET_CAPABILITY_IA:                   return "IA";
            case NET_CAPABILITY_RCS:                  return "RCS";
            case NET_CAPABILITY_XCAP:                 return "XCAP";
            case NET_CAPABILITY_EIMS:                 return "EIMS";
            case NET_CAPABILITY_NOT_METERED:          return "NOT_METERED";
            case NET_CAPABILITY_INTERNET:             return "INTERNET";
            case NET_CAPABILITY_NOT_RESTRICTED:       return "NOT_RESTRICTED";
            case NET_CAPABILITY_TRUSTED:              return "TRUSTED";
            case NET_CAPABILITY_NOT_VPN:              return "NOT_VPN";
            case NET_CAPABILITY_VALIDATED:            return "VALIDATED";
            case NET_CAPABILITY_CAPTIVE_PORTAL:       return "CAPTIVE_PORTAL";
            case NET_CAPABILITY_NOT_ROAMING:          return "NOT_ROAMING";
            case NET_CAPABILITY_FOREGROUND:           return "FOREGROUND";
            case NET_CAPABILITY_NOT_CONGESTED:        return "NOT_CONGESTED";
            case NET_CAPABILITY_NOT_SUSPENDED:        return "NOT_SUSPENDED";
            case NET_CAPABILITY_OEM_PAID:             return "OEM_PAID";
            case NET_CAPABILITY_MCX:                  return "MCX";
            case NET_CAPABILITY_PARTIAL_CONNECTIVITY: return "PARTIAL_CONNECTIVITY";
            case NET_CAPABILITY_TEMPORARILY_NOT_METERED:    return "TEMPORARILY_NOT_METERED";
            case NET_CAPABILITY_OEM_PRIVATE:          return "OEM_PRIVATE";
            case NET_CAPABILITY_VEHICLE_INTERNAL:     return "VEHICLE_INTERNAL";
            case NET_CAPABILITY_NOT_VCN_MANAGED:      return "NOT_VCN_MANAGED";
            case NET_CAPABILITY_ENTERPRISE:           return "ENTERPRISE";
            case NET_CAPABILITY_VSIM:                 return "VSIM";
            case NET_CAPABILITY_BIP:                  return "BIP";
            case NET_CAPABILITY_HEAD_UNIT:            return "HEAD_UNIT";
            case NET_CAPABILITY_MMTEL:                return "MMTEL";
            case NET_CAPABILITY_PRIORITIZE_LATENCY:          return "PRIORITIZE_LATENCY";
            case NET_CAPABILITY_PRIORITIZE_BANDWIDTH:        return "PRIORITIZE_BANDWIDTH";
            case NET_CAPABILITY_LOCAL_NETWORK:        return "LOCAL_NETWORK";
            case NET_CAPABILITY_NOT_BANDWIDTH_CONSTRAINED:    return "NOT_BANDWIDTH_CONSTRAINED";
            default:                                  return Integer.toString(capability);
        }
    }

    private static @NonNull String enterpriseIdNameOf(
            @NetCapability int capability) {
        return Integer.toString(capability);
    }

    /**
     * @hide
     */
    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
    public static @NonNull String transportNamesOf(@Nullable @Transport int[] types) {
        StringJoiner joiner = new StringJoiner("|");
        if (types != null) {
            for (int t : types) {
                joiner.add(transportNameOf(t));
            }
        }
        return joiner.toString();
    }

    /**
     * @hide
     */
    public static @NonNull String transportNameOf(@Transport int transport) {
        if (!isValidTransport(transport)) {
            return "UNKNOWN";
        }
        return TRANSPORT_NAMES[transport];
    }

    private static void checkValidTransportType(@Transport int transport) {
        if (!isValidTransport(transport)) {
            throw new IllegalArgumentException("Invalid TransportType " + transport);
        }
    }

    private static boolean isValidCapability(@NetworkCapabilities.NetCapability int capability) {
        return capability >= 0 && capability <= MAX_NET_CAPABILITY;
    }

    private static boolean isValidEnterpriseId(
            @NetworkCapabilities.EnterpriseId int enterpriseId) {
        return enterpriseId >= NET_ENTERPRISE_ID_1
                && enterpriseId <= NET_ENTERPRISE_ID_5;
    }

    private static void checkValidEnterpriseId(
            @NetworkCapabilities.EnterpriseId int enterpriseId) {
        if (!isValidEnterpriseId(enterpriseId)) {
            throw new IllegalArgumentException("enterprise capability identifier "
                    + enterpriseId + " is out of range");
        }
    }

    /**
     * Check if this {@code NetworkCapability} instance is metered.
     *
     * @return {@code true} if {@code NET_CAPABILITY_NOT_METERED} is not set on this instance.
     * @hide
     */
    public boolean isMetered() {
        return !hasCapability(NET_CAPABILITY_NOT_METERED);
    }

    /**
     * Check if private dns is broken.
     *
     * @return {@code true} if private DNS is broken on this network.
     * @hide
     */
    @SystemApi
    public boolean isPrivateDnsBroken() {
        return mPrivateDnsBroken;
    }

    /**
     * Set mPrivateDnsBroken to true when private dns is broken.
     *
     * @param broken the status of private DNS to be set.
     * @hide
     */
    public void setPrivateDnsBroken(boolean broken) {
        mPrivateDnsBroken = broken;
    }

    private boolean equalsPrivateDnsBroken(NetworkCapabilities nc) {
        return mPrivateDnsBroken == nc.mPrivateDnsBroken;
    }

    /**
     * Set the UID of the app making the request.
     *
     * For instances of NetworkCapabilities representing a request, sets the
     * UID of the app making the request. For a network created by the system,
     * sets the UID of the only app whose requests can match this network.
     * This can be set to {@link Process#INVALID_UID} if there is no such app,
     * or if this instance of NetworkCapabilities is about to be sent to a
     * party that should not learn about this.
     *
     * @param uid UID of the app.
     * @hide
     */
    public @NonNull NetworkCapabilities setRequestorUid(int uid) {
        mRequestorUid = uid;
        return this;
    }

    /**
     * Returns the UID of the app making the request.
     *
     * For a NetworkRequest being made by an app, contains the app's UID. For a network
     * created by the system, contains the UID of the only app whose requests can match
     * this network, or {@link Process#INVALID_UID} if none or if the
     * caller does not have permission to learn about this.
     *
     * @return the uid of the app making the request.
     * @hide
     */
    public int getRequestorUid() {
        return mRequestorUid;
    }

    /**
     * Set the package name of the app making the request.
     *
     * For instances of NetworkCapabilities representing a request, sets the
     * package name of the app making the request. For a network created by the system,
     * sets the package name of the only app whose requests can match this network.
     * This can be set to null if there is no such app, or if this instance of
     * NetworkCapabilities is about to be sent to a party that should not learn about this.
     *
     * @param packageName package name of the app.
     * @hide
     */
    public @NonNull NetworkCapabilities setRequestorPackageName(@NonNull String packageName) {
        mRequestorPackageName = packageName;
        return this;
    }

    /**
     * Returns the package name of the app making the request.
     *
     * For a NetworkRequest being made by an app, contains the app's package name. For a
     * network created by the system, contains the package name of the only app whose
     * requests can match this network, or null if none or if the caller does not have
     * permission to learn about this.
     *
     * @return the package name of the app making the request.
     * @hide
     */
    @Nullable
    public String getRequestorPackageName() {
        return mRequestorPackageName;
    }

    /**
     * Set the uid and package name of the app causing this network to exist.
     *
     * See {@link #setRequestorUid} and {@link #setRequestorPackageName}
     *
     * @param uid UID of the app.
     * @param packageName package name of the app.
     * @hide
     */
    public @NonNull NetworkCapabilities setRequestorUidAndPackageName(
            int uid, @NonNull String packageName) {
        return setRequestorUid(uid).setRequestorPackageName(packageName);
    }

    /**
     * Test whether the passed NetworkCapabilities satisfies the requestor restrictions of this
     * capabilities.
     *
     * This method is called on the NetworkCapabilities embedded in a request with the
     * capabilities of an available network. If the available network, sets a specific
     * requestor (by uid and optionally package name), then this will only match a request from the
     * same app. If either of the capabilities have an unset uid or package name, then it matches
     * everything.
     * <p>
     * nc is assumed nonnull. Else, NPE.
     */
    private boolean satisfiedByRequestor(NetworkCapabilities nc) {
        // No uid set, matches everything.
        if (mRequestorUid == Process.INVALID_UID || nc.mRequestorUid == Process.INVALID_UID) {
            return true;
        }
        // uids don't match.
        if (mRequestorUid != nc.mRequestorUid) return false;
        // No package names set, matches everything
        if (null == nc.mRequestorPackageName || null == mRequestorPackageName) return true;
        // check for package name match.
        return TextUtils.equals(mRequestorPackageName, nc.mRequestorPackageName);
    }

    private boolean equalsRequestor(NetworkCapabilities nc) {
        return mRequestorUid == nc.mRequestorUid
                && TextUtils.equals(mRequestorPackageName, nc.mRequestorPackageName);
    }

    /**
     * Set of the subscription IDs that identifies the network or request, empty if none.
     */
    @NonNull
    private ArraySet<Integer> mSubIds = new ArraySet<>();

    /**
     * Sets the subscription ID set that associated to this network or request.
     *
     * @hide
     */
    @NonNull
    public NetworkCapabilities setSubscriptionIds(@NonNull Set<Integer> subIds) {
        mSubIds = new ArraySet(Objects.requireNonNull(subIds));
        return this;
    }

    /**
     * Gets the subscription ID set that associated to this network or request.
     *
     * <p>Instances of NetworkCapabilities will only have this field populated by the system if the
     * receiver holds the NETWORK_FACTORY permission. In all other cases, it will be the empty set.
     *
     * @return
     */
    @NonNull
    @FlaggedApi(Flags.REQUEST_RESTRICTED_WIFI)
    public Set<Integer> getSubscriptionIds() {
        return new ArraySet<>(mSubIds);
    }

    /**
     * Tests if the subscription ID set of this network is the same as that of the passed one.
     */
    private boolean equalsSubscriptionIds(@NonNull NetworkCapabilities nc) {
        return Objects.equals(mSubIds, nc.mSubIds);
    }

    /**
     * Check if the subscription ID set requirements of this object are matched by the passed one.
     * If specified in the request, the passed one need to have at least one subId and at least
     * one of them needs to be in the request set.
     */
    private boolean satisfiedBySubscriptionIds(@NonNull NetworkCapabilities nc) {
        if (mSubIds.isEmpty()) return true;
        if (nc.mSubIds.isEmpty()) return false;
        for (final Integer subId : nc.mSubIds) {
            if (mSubIds.contains(subId)) return true;
        }
        return false;
    }

    /**
     * Returns a bitmask of all the applicable redactions (based on the permissions held by the
     * receiving app) to be performed on this object.
     *
     * @return bitmask of redactions applicable on this instance.
     * @hide
     */
    public @RedactionType long getApplicableRedactions() {
        // Currently, there are no fields redacted in NetworkCapabilities itself, so we just
        // passthrough the redactions required by the embedded TransportInfo. If this changes
        // in the future, modify this method.
        if (mTransportInfo == null) {
            return NetworkCapabilities.REDACT_NONE;
        }
        return mTransportInfo.getApplicableRedactions();
    }

    private NetworkCapabilities removeDefaultCapabilites() {
        mNetworkCapabilities &= ~DEFAULT_CAPABILITIES;
        return this;
    }

    /**
     * Builder class for NetworkCapabilities.
     *
     * This class is mainly for {@link NetworkAgent} instances to use. Many fields in
     * the built class require holding a signature permission to use - mostly
     * {@link android.Manifest.permission.NETWORK_FACTORY}, but refer to the specific
     * description of each setter. As this class lives entirely in app space it does not
     * enforce these restrictions itself but the system server clears out the relevant
     * fields when receiving a NetworkCapabilities object from a caller without the
     * appropriate permission.
     *
     * Apps don't use this builder directly. Instead, they use {@link NetworkRequest} via
     * its builder object.
     *
     * @hide
     */
    @SystemApi
    public static final class Builder {
        private final NetworkCapabilities mCaps;

        /**
         * Creates a new Builder to construct NetworkCapabilities objects.
         */
        public Builder() {
            mCaps = new NetworkCapabilities();
        }

        /**
         * Creates a new Builder of NetworkCapabilities from an existing instance.
         */
        public Builder(@NonNull final NetworkCapabilities nc) {
            Objects.requireNonNull(nc);
            mCaps = new NetworkCapabilities(nc);
        }

        /**
         * Creates a new Builder without the default capabilities.
         */
        @NonNull
        public static Builder withoutDefaultCapabilities() {
            final NetworkCapabilities nc = new NetworkCapabilities();
            nc.removeDefaultCapabilites();
            return new Builder(nc);
        }

        /**
         * Adds the given transport type.
         *
         * Multiple transports may be added. Note that when searching for a network to satisfy a
         * request, satisfying any of the transports listed in the request will satisfy the request.
         * For example {@code TRANSPORT_WIFI} and {@code TRANSPORT_ETHERNET} added to a
         * {@code NetworkCapabilities} would cause either a Wi-Fi network or an Ethernet network
         * to be selected. This is logically different than
         * {@code NetworkCapabilities.NET_CAPABILITY_*}. Also note that multiple networks with the
         * same transport type may be active concurrently.
         *
         * @param transportType the transport type to be added or removed.
         * @return this builder
         */
        @NonNull
        public Builder addTransportType(@Transport int transportType) {
            checkValidTransportType(transportType);
            mCaps.addTransportType(transportType);
            return this;
        }

        /**
         * Removes the given transport type.
         *
         * @see #addTransportType
         *
         * @param transportType the transport type to be added or removed.
         * @return this builder
         */
        @NonNull
        public Builder removeTransportType(@Transport int transportType) {
            checkValidTransportType(transportType);
            mCaps.removeTransportType(transportType);
            return this;
        }

        /**
         * Adds the given capability.
         *
         * @param capability the capability
         * @return this builder
         */
        @NonNull
        public Builder addCapability(@NetCapability final int capability) {
            mCaps.setCapability(capability, true);
            return this;
        }

        /**
         * Removes the given capability.
         *
         * @param capability the capability
         * @return this builder
         */
        @NonNull
        public Builder removeCapability(@NetCapability final int capability) {
            mCaps.setCapability(capability, false);
            return this;
        }

        /**
         * Adds the given capability to the list of forbidden capabilities.
         *
         * A network with a capability will not match a {@link NetworkCapabilities} or
         * {@link NetworkRequest} which has said capability set as forbidden. For example, if
         * a request has NET_CAPABILITY_INTERNET in the list of forbidden capabilities, networks
         * with NET_CAPABILITY_INTERNET will not match the request.
         *
         * If the capability was previously added to the list of required capabilities (for
         * example, it was there by default or added using {@link #addCapability(int)} method), then
         * it will be removed from the list of required capabilities as well.
         *
         * @param capability the capability
         * @return this builder
         * @hide
         */
        @NonNull
        // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public
        public Builder addForbiddenCapability(@NetCapability final int capability) {
            mCaps.addForbiddenCapability(capability);
            return this;
        }

        /**
         * Removes the given capability from the list of forbidden capabilities.
         *
         * @see #addForbiddenCapability(int)
         * @param capability the capability
         * @return this builder
         * @hide
         */
        @NonNull
        // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public
        public Builder removeForbiddenCapability(@NetCapability final int capability) {
            mCaps.removeForbiddenCapability(capability);
            return this;
        }

        /**
         * Adds the given enterprise capability identifier.
         * Note that when searching for a network to satisfy a request, all capabilities identifier
         * requested must be satisfied. Enterprise capability identifier is applicable only
         * for NET_CAPABILITY_ENTERPRISE capability
         *
         * @param enterpriseId enterprise capability identifier.
         *
         * @return this builder
         */
        @NonNull
        public Builder addEnterpriseId(
                @EnterpriseId  int enterpriseId) {
            mCaps.addEnterpriseId(enterpriseId);
            return this;
        }

        /**
         * Removes the given enterprise capability identifier. Enterprise capability identifier is
         * applicable only for NET_CAPABILITY_ENTERPRISE capability
         *
         * @param enterpriseId the enterprise capability identifier
         * @return this builder
         */
        @NonNull
        public Builder removeEnterpriseId(
                @EnterpriseId  int enterpriseId) {
            mCaps.removeEnterpriseId(enterpriseId);
            return this;
        }

        /**
         * Sets the owner UID.
         *
         * The default value is {@link Process#INVALID_UID}. Pass this value to reset.
         *
         * Note: for security the system will clear out this field when received from a
         * non-privileged source.
         *
         * @param ownerUid the owner UID
         * @return this builder
         */
        @NonNull
        @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
        public Builder setOwnerUid(final int ownerUid) {
            mCaps.setOwnerUid(ownerUid);
            return this;
        }

        /**
         * Sets the list of UIDs that are administrators of this network.
         *
         * <p>UIDs included in administratorUids gain administrator privileges over this
         * Network. Examples of UIDs that should be included in administratorUids are:
         * <ul>
         *     <li>Carrier apps with privileges for the relevant subscription
         *     <li>Active VPN apps
         *     <li>Other application groups with a particular Network-related role
         * </ul>
         *
         * <p>In general, user-supplied networks (such as WiFi networks) do not have
         * administrators.
         *
         * <p>An app is granted owner privileges over Networks that it supplies. The owner
         * UID MUST always be included in administratorUids.
         *
         * The default value is the empty array. Pass an empty array to reset.
         *
         * Note: for security the system will clear out this field when received from a
         * non-privileged source, such as an app using reflection to call this or
         * mutate the member in the built object.
         *
         * @param administratorUids the UIDs to be set as administrators of this Network.
         * @return this builder
         */
        @NonNull
        @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
        public Builder setAdministratorUids(@NonNull final int[] administratorUids) {
            Objects.requireNonNull(administratorUids);
            mCaps.setAdministratorUids(administratorUids);
            return this;
        }

        /**
         * Sets the upstream bandwidth of the link.
         *
         * Sets the upstream bandwidth for this network in Kbps. This always only refers to
         * the estimated first hop transport bandwidth.
         * <p>
         * Note that when used to request a network, this specifies the minimum acceptable.
         * When received as the state of an existing network this specifies the typical
         * first hop bandwidth expected. This is never measured, but rather is inferred
         * from technology type and other link parameters. It could be used to differentiate
         * between very slow 1xRTT cellular links and other faster networks or even between
         * 802.11b vs 802.11AC wifi technologies. It should not be used to differentiate between
         * fast backhauls and slow backhauls.
         *
         * @param upKbps the estimated first hop upstream (device to network) bandwidth.
         * @return this builder
         */
        @NonNull
        public Builder setLinkUpstreamBandwidthKbps(final int upKbps) {
            mCaps.setLinkUpstreamBandwidthKbps(upKbps);
            return this;
        }

        /**
         * Sets the downstream bandwidth for this network in Kbps. This always only refers to
         * the estimated first hop transport bandwidth.
         * <p>
         * Note that when used to request a network, this specifies the minimum acceptable.
         * When received as the state of an existing network this specifies the typical
         * first hop bandwidth expected. This is never measured, but rather is inferred
         * from technology type and other link parameters. It could be used to differentiate
         * between very slow 1xRTT cellular links and other faster networks or even between
         * 802.11b vs 802.11AC wifi technologies. It should not be used to differentiate between
         * fast backhauls and slow backhauls.
         *
         * @param downKbps the estimated first hop downstream (network to device) bandwidth.
         * @return this builder
         */
        @NonNull
        public Builder setLinkDownstreamBandwidthKbps(final int downKbps) {
            mCaps.setLinkDownstreamBandwidthKbps(downKbps);
            return this;
        }

        /**
         * Sets the optional bearer specific network specifier.
         * This has no meaning if a single transport is also not specified, so calling
         * this without a single transport set will generate an exception, as will
         * subsequently adding or removing transports after this is set.
         * </p>
         *
         * @param specifier a concrete, parcelable framework class that extends NetworkSpecifier,
         *        or null to clear it.
         * @return this builder
         */
        @NonNull
        public Builder setNetworkSpecifier(@Nullable final NetworkSpecifier specifier) {
            mCaps.setNetworkSpecifier(specifier);
            return this;
        }

        /**
         * Sets the optional transport specific information.
         *
         * @param info A concrete, parcelable framework class that extends {@link TransportInfo},
         *             or null to clear it.
         * @return this builder
         */
        @NonNull
        public Builder setTransportInfo(@Nullable final TransportInfo info) {
            mCaps.setTransportInfo(info);
            return this;
        }

        /**
         * Sets the signal strength. This is a signed integer, with higher values indicating a
         * stronger signal. The exact units are bearer-dependent. For example, Wi-Fi uses the
         * same RSSI units reported by wifi code.
         * <p>
         * Note that when used to register a network callback, this specifies the minimum
         * acceptable signal strength. When received as the state of an existing network it
         * specifies the current value. A value of code SIGNAL_STRENGTH_UNSPECIFIED} means
         * no value when received and has no effect when requesting a callback.
         *
         * Note: for security the system will throw if it receives a NetworkRequest where
         * the underlying NetworkCapabilities has this member set from a source that does
         * not hold the {@link android.Manifest.permission.NETWORK_SIGNAL_STRENGTH_WAKEUP}
         * permission. Apps with this permission can use this indirectly through
         * {@link android.net.NetworkRequest}.
         *
         * @param signalStrength the bearer-specific signal strength.
         * @return this builder
         */
        @NonNull
        @RequiresPermission(android.Manifest.permission.NETWORK_SIGNAL_STRENGTH_WAKEUP)
        public Builder setSignalStrength(final int signalStrength) {
            mCaps.setSignalStrength(signalStrength);
            return this;
        }

        /**
         * Sets the SSID of this network.
         *
         * Note: for security the system will clear out this field when received from a
         * non-privileged source, like an app using reflection to set this.
         *
         * @param ssid the SSID, or null to clear it.
         * @return this builder
         */
        @NonNull
        @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
        public Builder setSsid(@Nullable final String ssid) {
            mCaps.setSSID(ssid);
            return this;
        }

        /**
         * Set the uid of the app causing this network to exist.
         *
         * Note: for security the system will clear out this field when received from a
         * non-privileged source.
         *
         * @param uid UID of the app.
         * @return this builder
         */
        @NonNull
        @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
        public Builder setRequestorUid(final int uid) {
            mCaps.setRequestorUid(uid);
            return this;
        }

        /**
         * Set the package name of the app causing this network to exist.
         *
         * Note: for security the system will clear out this field when received from a
         * non-privileged source.
         *
         * @param packageName package name of the app, or null to clear it.
         * @return this builder
         */
        @NonNull
        @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
        public Builder setRequestorPackageName(@Nullable final String packageName) {
            mCaps.setRequestorPackageName(packageName);
            return this;
        }

        /**
         * Set the subscription ID set.
         *
         * <p>SubIds are populated in NetworkCapability instances from the system only for callers
         * that hold the NETWORK_FACTORY permission. Similarly, the system will reject any
         * NetworkRequests filed with a non-empty set of subIds unless the caller holds the
         * NETWORK_FACTORY permission.
         *
         * @param subIds a set that represent the subscription IDs. Empty if clean up.
         * @return this builder.
         * @hide
         */
        @NonNull
        @SystemApi
        public Builder setSubscriptionIds(@NonNull final Set<Integer> subIds) {
            mCaps.setSubscriptionIds(subIds);
            return this;
        }

        /**
         * Set the list of UIDs this network applies to.
         *
         * @param uids the list of UIDs this network applies to, or {@code null} if this network
         *             applies to all UIDs.
         * @return this builder
         * @hide
         */
        @NonNull
        @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
        public Builder setUids(@Nullable Set<Range<Integer>> uids) {
            mCaps.setUids(uids);
            return this;
        }

        /**
         * Set a list of UIDs that can always access this network
         * <p>
         * Provide a list of UIDs that can access this network even if the network doesn't have the
         * {@link #NET_CAPABILITY_NOT_RESTRICTED} capability and the UID does not hold the
         * {@link android.Manifest.permission.CONNECTIVITY_USE_RESTRICTED_NETWORKS} permission.
         * <p>
         * This is disallowed in {@link NetworkRequest}, and can only be set by
         * {@link NetworkAgent}s, who hold the
         * {@link android.Manifest.permission.NETWORK_FACTORY} permission.
         * Network agents also have restrictions on how they can set these ; they can only back
         * a public Android API. As such, Ethernet agents can set this when backing the per-UID
         * access API, and Telephony can set exactly one UID which has to match the manager app for
         * the associated subscription. Failure to comply with these rules will see this member
         * cleared.
         * <p>
         * These UIDs are only visible to network factories and the system server, since the system
         * server makes sure to redact them before sending a {@link NetworkCapabilities} instance
         * to a process that doesn't hold the {@link android.Manifest.permission.NETWORK_FACTORY}
         * permission.
         * <p>
         * This list cannot be null, but it can be empty to mean that no UID without the
         * {@link android.Manifest.permission.CONNECTIVITY_USE_RESTRICTED_NETWORKS} permission
         * can access this network.
         *
         * @param uids the list of UIDs that can always access this network
         * @return this builder
         * @hide
         */
        @NonNull
        @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
        @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
        public Builder setAllowedUids(@NonNull Set<Integer> uids) {
            Objects.requireNonNull(uids);
            mCaps.setAllowedUids(uids);
            return this;
        }

        /**
         * Set the underlying networks of this network.
         *
         * <p>This API is mainly for {@link NetworkAgent}s who hold
         * {@link android.Manifest.permission.NETWORK_FACTORY} to set its underlying networks.
         *
         * <p>The underlying networks are only visible for the receiver who has one of
         * {@link android.Manifest.permission.NETWORK_FACTORY},
         * {@link android.Manifest.permission.NETWORK_SETTINGS} and
         * {@link NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK}.
         * If the receiver doesn't have required permissions, the field will be cleared before
         * sending to the caller.</p>
         *
         * @param networks The underlying networks of this network.
         */
        @NonNull
        @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
        public Builder setUnderlyingNetworks(@Nullable List<Network> networks) {
            mCaps.setUnderlyingNetworks(networks);
            return this;
        }

        /**
         * Builds the instance of the capabilities.
         *
         * @return the built instance of NetworkCapabilities.
         */
        @NonNull
        public NetworkCapabilities build() {
            if (mCaps.getOwnerUid() != Process.INVALID_UID) {
                if (!CollectionUtils.contains(mCaps.getAdministratorUids(), mCaps.getOwnerUid())) {
                    throw new IllegalStateException("The owner UID must be included in "
                            + " administrator UIDs.");
                }
            }

            if ((mCaps.getEnterpriseIds().length != 0)
                    && !mCaps.hasCapability(NET_CAPABILITY_ENTERPRISE)) {
                throw new IllegalStateException("Enterprise capability identifier is applicable"
                        + " only with ENTERPRISE capability.");
            }
            return new NetworkCapabilities(mCaps);
        }
    }
}