1 /*
2  * Copyright 2018 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.accessibilityservice.cts.utils;
18 
19 import android.app.Instrumentation;
20 
21 import java.util.concurrent.Callable;
22 import java.util.concurrent.atomic.AtomicReference;
23 
24 /**
25  * Utilities to return values from {@link Instrumentation#runOnMainSync()}
26  */
27 public class RunOnMainUtils {
28     /**
29      * Execute a callable on main and return its value
30      */
getOnMain( Instrumentation instrumentation, Callable<T> callable)31     public static <T extends Object> T getOnMain(
32             Instrumentation instrumentation, Callable<T> callable) {
33         AtomicReference<T> returnValue = new AtomicReference<>(null);
34         AtomicReference<Throwable> throwable = new AtomicReference<>(null);
35         instrumentation.runOnMainSync(() -> {
36             try {
37                 returnValue.set(callable.call());
38             } catch (Throwable e) {
39                 throwable.set(e);
40             }
41         });
42         if (throwable.get() != null) {
43             throw new RuntimeException(throwable.get());
44         }
45         return returnValue.get();
46     }
47 }
48