content: /*
   * 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.platform.app.InstrumentationRegistry.getInstrumentation;
  
  import android.os.Looper;
  import android.util.Log;
  import java.lang.annotation.Annotation;
  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 base;
  
    private final boolean runOnUiThread;
  
    public UiThreadStatement(Statement base, boolean runOnUiThread) {
      this.base = base;
      this.runOnUiThread = runOnUiThread;
    }
  
    public boolean isRunOnUiThread() {
      return runOnUiThread;
    }
  
    @Override
    public void evaluate() throws Throwable {
      if (runOnUiThread) {
        final AtomicReference<Throwable> exceptionRef = new AtomicReference<>();
        runOnUiThread(
            new Runnable() {
              @Override
              public void run() {
                try {
                  base.evaluate();
                } catch (Throwable throwable) {
                  exceptionRef.set(throwable);
                }
              }
            });
        Throwable throwable = exceptionRef.get();
        if (throwable != null) {
          throw throwable;
        }
      } else {
        base.evaluate();
      }
    }
  
    public static boolean shouldRunOnUiThread(FrameworkMethod method) {
      Class<? extends Annotation> deprecatedUiThreadTestClass =
          loadUiThreadClass("android.test.UiThreadTest");
      if (hasAnnotation(method, deprecatedUiThreadTestClass)) {
        return true;
      } else {
        // to avoid circular dependency on Rules module use the class name directly
        @SuppressWarnings("unchecked") // reflection
        Class<? extends Annotation> uiThreadTestClass =
            loadUiThreadClass("androidx.test.annotation.UiThreadTest");
        if (hasAnnotation(method, deprecatedUiThreadTestClass)
            || hasAnnotation(method, uiThreadTestClass)) {
            return true;
          }
      }
      return false;
    }
  
    private static boolean hasAnnotation(
        FrameworkMethod method, Class<? extends Annotation> annotationClass) {
      return annotationClass != null
          && (method.getAnnotation(annotationClass) != null
              || classHasAnnotation(method, annotationClass));
    }
  
    private static boolean classHasAnnotation(
        FrameworkMethod method, Class<? extends Annotation> annotationClass) {
      Class<?> declaringClass = method.getDeclaringClass();
  
      for (Class<?> declaredInterface : declaringClass.getInterfaces()) {
        if (declaredInterface.isAnnotationPresent(annotationClass)) {
          return true;
        }
      }
  
      while (declaringClass != null) {
        if (declaringClass.isAnnotationPresent(annotationClass)) {
          return true;
        }
  
        declaringClass = declaringClass.getSuperclass();
      }
  
      return false;
    }
  
    private static Class<? extends Annotation> loadUiThreadClass(String className) {
      try {
        return (Class<? extends Annotation>) Class.forName(className);
      } catch (ClassNotFoundException e) {
        return null;
      }
    }
  
    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();
        }
      }
    }
  }
  