Java example source code file (FutureCallbackTest.java)

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Java - Java tags/keywords

annotation, countingsamethreadexecutor, futurecallback, gwtincompatible, illegalargumentexception, listenablefuture, mockcallback, mockito, nullable, override, runtimeexception, safe, settablefuture, string, testerror, threading, threads

The FutureCallbackTest.java Java example source code

/*
 * Copyright (C) 2011 The Guava Authors
 *
 * 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 com.google.common.util.concurrent;

import static com.google.common.truth.Truth.assertThat;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;

import junit.framework.TestCase;

import org.mockito.Mockito;

import java.util.concurrent.CancellationException;
import java.util.concurrent.Executor;

import javax.annotation.Nullable;

/**
 * Test for {@link FutureCallback}.
 *
 * @author Anthony Zana
 */
@GwtCompatible(emulated = true)
public class FutureCallbackTest extends TestCase {
  public void testSameThreadSuccess() {
    SettableFuture<String> f = SettableFuture.create();
    MockCallback callback = new MockCallback("foo");
    Futures.addCallback(f, callback);
    f.set("foo");
  }

  public void testExecutorSuccess() {
    CountingSameThreadExecutor ex = new CountingSameThreadExecutor();
    SettableFuture<String> f = SettableFuture.create();
    MockCallback callback = new MockCallback("foo");
    Futures.addCallback(f, callback, ex);
    f.set("foo");
    assertEquals(1, ex.runCount);
  }

  // Error cases
  public void testSameThreadExecutionException() {
    SettableFuture<String> f = SettableFuture.create();
    Exception e = new IllegalArgumentException("foo not found");
    MockCallback callback = new MockCallback(e);
    Futures.addCallback(f, callback);
    f.setException(e);
  }

  public void testCancel() {
    SettableFuture<String> f = SettableFuture.create();
    FutureCallback<String> callback =
        new FutureCallback<String>() {
          private boolean called = false;

          @Override
          public void onSuccess(String result) {
            fail("Was not expecting onSuccess() to be called.");
          }

          @Override
          public synchronized void onFailure(Throwable t) {
            assertFalse(called);
            assertThat(t).isInstanceOf(CancellationException.class);
            called = true;
          }
        };
    Futures.addCallback(f, callback);
    f.cancel(true);
  }

  public void testThrowErrorFromGet() {
    Error error = new AssertionError("ASSERT!");
    ListenableFuture<String> f = UncheckedThrowingFuture.throwingError(error);
    MockCallback callback = new MockCallback(error);
    Futures.addCallback(f, callback);
  }

  public void testRuntimeExeceptionFromGet() {
    RuntimeException e = new IllegalArgumentException("foo not found");
    ListenableFuture<String> f = UncheckedThrowingFuture.throwingRuntimeException(e);
    MockCallback callback = new MockCallback(e);
    Futures.addCallback(f, callback);
  }

  @GwtIncompatible // Mockito
  public void testOnSuccessThrowsRuntimeException() throws Exception {
    RuntimeException exception = new RuntimeException();
    String result = "result";
    SettableFuture<String> future = SettableFuture.create();
    @SuppressWarnings("unchecked") // Safe for a mock
    FutureCallback<String> callback = Mockito.mock(FutureCallback.class);
    Futures.addCallback(future, callback);
    Mockito.doThrow(exception).when(callback).onSuccess(result);
    future.set(result);
    assertEquals(result, future.get());
    Mockito.verify(callback).onSuccess(result);
    Mockito.verifyNoMoreInteractions(callback);
  }

  @GwtIncompatible // Mockito
  public void testOnSuccessThrowsError() throws Exception {
    class TestError extends Error {}
    TestError error = new TestError();
    String result = "result";
    SettableFuture<String> future = SettableFuture.create();
    @SuppressWarnings("unchecked") // Safe for a mock
    FutureCallback<String> callback = Mockito.mock(FutureCallback.class);
    Futures.addCallback(future, callback);
    Mockito.doThrow(error).when(callback).onSuccess(result);
    try {
      future.set(result);
      fail("Should have thrown");
    } catch (TestError e) {
      assertSame(error, e);
    }
    assertEquals(result, future.get());
    Mockito.verify(callback).onSuccess(result);
    Mockito.verifyNoMoreInteractions(callback);
  }

  public void testWildcardFuture() {
    SettableFuture<String> settable = SettableFuture.create();
    ListenableFuture<?> f = settable;
    FutureCallback<Object> callback = new FutureCallback