UiThreadStatement.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 androidx.test.internal.runner.junit4.statement;
import static androidx.test.InstrumentationRegistry.getInstrumentation;
import android.os.Looper;
import android.util.Log;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.FutureTask;
import java.util.concurrent.atomic.AtomicReference;
import org.junit.runners.model.FrameworkMethod;
import org.junit.runners.model.Statement;
/** {@link Statement} that executes a test on the application's main thread (or UI thread). */
public class UiThreadStatement extends Statement {
private static final String TAG = "UiThreadStatement";
private final Statement mBase;
private final boolean mRunOnUiThread;
public UiThreadStatement(Statement base, boolean runOnUiThread) {
mBase = base;
mRunOnUiThread = runOnUiThread;
}
public boolean isRunOnUiThread() {
return mRunOnUiThread;
}
@Override
public void evaluate() throws Throwable {
if (mRunOnUiThread) {
final AtomicReference<Throwable> exceptionRef = new AtomicReference<>();
runOnUiThread(
new Runnable() {
@Override
public void run() {
try {
mBase.evaluate();
} catch (Throwable throwable) {
exceptionRef.set(throwable);
}
}
});
Throwable throwable = exceptionRef.get();
if (throwable != null) {
throw throwable;
}
} else {
mBase.evaluate();
}
}
public static boolean shouldRunOnUiThread(FrameworkMethod method) {
Class<android.test.UiThreadTest> deprecatedUiThreadTestClass = android.test.UiThreadTest.class;
if (method.getAnnotation(deprecatedUiThreadTestClass) != null) {
return true;
} else {
try {
// to avoid circular dependency on Rules module use the class name directly
@SuppressWarnings("unchecked") // reflection
Class UiThreadTestClass = Class.forName("androidx.test.annotation.UiThreadTest");
if (method.getAnnotation(deprecatedUiThreadTestClass) != null
|| method.getAnnotation(UiThreadTestClass) != null) {
return true;
}
} catch (ClassNotFoundException e) {
// ignore, annotation is not used.
}
}
return false;
}
public static void runOnUiThread(final Runnable runnable) throws Throwable {
if (Looper.myLooper() == Looper.getMainLooper()) {
Log.w(
TAG,
"Already on the UI thread, this method should not be called from the "
+ "main application thread");
runnable.run();
} else {
FutureTask<Void> task = new FutureTask<>(runnable, null);
getInstrumentation().runOnMainSync(task);
try {
task.get();
} catch (ExecutionException e) {
// Expose the original exception
throw e.getCause();
}
}
}
}