content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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 org.apache.beam.runners.portability;
  
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.hamcrest.Matchers.is;
  import static org.junit.Assert.fail;
  
  import java.util.concurrent.atomic.AtomicBoolean;
  import org.apache.beam.runners.portability.CloseableResource.CloseException;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.rules.ExpectedException;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  
  /** Tests for {@link CloseableResource}. */
  @RunWith(JUnit4.class)
  public class CloseableResourceTest {
    @Rule public ExpectedException thrown = ExpectedException.none();
  
    @Test
    public void alwaysReturnsSameResource() {
      Foo foo = new Foo();
      CloseableResource<Foo> resource = CloseableResource.of(foo, ignored -> {});
      assertThat(resource.get(), is(foo));
      assertThat(resource.get(), is(foo));
    }
  
    @Test
    public void callsCloser() throws Exception {
      AtomicBoolean closed = new AtomicBoolean(false);
      try (CloseableResource<Foo> ignored =
          CloseableResource.of(new Foo(), foo -> closed.set(true))) {
        // Do nothing.
      }
      assertThat(closed.get(), is(true));
    }
  
    @Test
    public void wrapsExceptionsInCloseException() throws Exception {
      Exception wrapped = new Exception();
      thrown.expect(CloseException.class);
      thrown.expectCause(is(wrapped));
      try (CloseableResource<Foo> ignored =
          CloseableResource.of(
              new Foo(),
              foo -> {
                throw wrapped;
              })) {
        // Do nothing.
      }
    }
  
    @Test
    public void transferReleasesCloser() throws Exception {
      try (CloseableResource<Foo> foo =
          CloseableResource.of(
              new Foo(), unused -> fail("Transferred resource should not be closed"))) {
        foo.transfer();
      }
    }
  
    @Test
    public void transferMovesOwnership() throws Exception {
      AtomicBoolean closed = new AtomicBoolean(false);
      CloseableResource<Foo> original = CloseableResource.of(new Foo(), unused -> closed.set(true));
      CloseableResource<Foo> transferred = original.transfer();
      transferred.close();
      assertThat(closed.get(), is(true));
    }
  
    @Test
    public void cannotTransferClosed() throws Exception {
      CloseableResource<Foo> foo = CloseableResource.of(new Foo(), unused -> {});
      foo.close();
      thrown.expect(IllegalStateException.class);
      foo.transfer();
    }
  
    @Test
    public void cannotTransferTwice() {
      CloseableResource<Foo> foo = CloseableResource.of(new Foo(), unused -> {});
      foo.transfer();
      thrown.expect(IllegalStateException.class);
      foo.transfer();
    }
  
    private static class Foo {}
  }
  