1 /*
2  * Copyright (C) 2023 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.adservices.ondevicepersonalization;
18 
19 import android.annotation.FlaggedApi;
20 import android.annotation.NonNull;
21 import android.annotation.Nullable;
22 import android.annotation.WorkerThread;
23 
24 import com.android.adservices.ondevicepersonalization.flags.Flags;
25 
26 /**
27  * An interface to a read-write key-value store.
28  *
29  * Used as a Data Access Object for the LOCAL_DATA table.
30  *
31  * @see IsolatedService#getLocalData(RequestToken)
32  *
33  */
34 @FlaggedApi(Flags.FLAG_ON_DEVICE_PERSONALIZATION_APIS_ENABLED)
35 public interface MutableKeyValueStore extends KeyValueStore {
36     /**
37      * Associates the specified value with the specified key.
38      * If a value already exists for that key, the old value is replaced.
39      *
40      * @param key key with which the specified value is to be associated
41      * @param value value to be associated with the specified key
42      *
43      * @return the previous value associated with key, or null if there was no mapping for key.
44      */
45     @WorkerThread
put(@onNull String key, @NonNull byte[] value)46     @Nullable byte[] put(@NonNull String key, @NonNull byte[] value);
47 
48     /**
49      * Removes the mapping for the specified key.
50      *
51      * @param key key whose mapping is to be removed
52      *
53      * @return the previous value associated with key, or null if there was no mapping for key.
54      */
55     @WorkerThread
remove(@onNull String key)56     @Nullable byte[] remove(@NonNull String key);
57 }
58