View Javadoc

1   /*
2    * Copyright 2013 The Netty Project
3    *
4    * The Netty Project licenses this file to you under the Apache License,
5    * version 2.0 (the "License"); you may not use this file except in compliance
6    * with the License. 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, WITHOUT
12   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13   * License for the specific language governing permissions and limitations
14   * under the License.
15   */
16  package io.netty.util.concurrent;
17  
18  import java.util.concurrent.CancellationException;
19  import java.util.concurrent.ExecutionException;
20  import java.util.concurrent.TimeUnit;
21  import java.util.concurrent.TimeoutException;
22  
23  /**
24   * Abstract {@link Future} implementation which does not allow for cancellation.
25   *
26   * @param <V>
27   */
28  public abstract class AbstractFuture<V> implements Future<V> {
29  
30      @Override
31      public V get() throws InterruptedException, ExecutionException {
32          await();
33  
34          Throwable cause = cause();
35          if (cause == null) {
36              return getNow();
37          }
38          if (cause instanceof CancellationException) {
39              throw (CancellationException) cause;
40          }
41          throw new ExecutionException(cause);
42      }
43  
44      @Override
45      public V get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException {
46          if (await(timeout, unit)) {
47              Throwable cause = cause();
48              if (cause == null) {
49                  return getNow();
50              }
51              if (cause instanceof CancellationException) {
52                  throw (CancellationException) cause;
53              }
54              throw new ExecutionException(cause);
55          }
56          throw new TimeoutException();
57      }
58  }