1 /*
2  * Copyright (C) 2020 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.server.wm;
18 
19 import android.content.ComponentName;
20 import android.content.ServiceConnection;
21 import android.os.IBinder;
22 import android.os.IInterface;
23 import android.util.Log;
24 
25 import java.util.concurrent.CompletableFuture;
26 import java.util.concurrent.TimeUnit;
27 import java.util.function.Function;
28 
29 import javax.annotation.Nullable;
30 
31 public class FutureConnection<T extends IInterface> implements ServiceConnection {
32     private static final String TAG = "FutureServiceConnection";
33 
34     private final Function<IBinder, T> mConverter;
35     private volatile CompletableFuture<IBinder> mFuture = new CompletableFuture<>();
36 
FutureConnection(Function<IBinder, T> converter)37     public FutureConnection(Function<IBinder, T> converter) {
38         mConverter = converter;
39     }
40 
get(long timeoutMs)41     public T get(long timeoutMs) throws Exception {
42         return mConverter.apply(mFuture.get(timeoutMs, TimeUnit.MILLISECONDS));
43     }
44 
45     @Nullable
getCurrent()46     public T getCurrent() {
47         return mConverter.apply(mFuture.getNow(null));
48     }
49 
50     @Override
onServiceConnected(ComponentName name, IBinder service)51     public void onServiceConnected(ComponentName name, IBinder service) {
52         mFuture.complete(service);
53     }
54 
55     @Override
onServiceDisconnected(ComponentName name)56     public void onServiceDisconnected(ComponentName name) {
57         Log.w(TAG, name.flattenToShortString() + " disconnected");
58         mFuture = new CompletableFuture<>();
59     }
60 }
61