1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27 package org.apache.hc.core5.concurrent;
28
29 import java.util.concurrent.Future;
30 import java.util.concurrent.TimeUnit;
31
32 import org.apache.hc.core5.annotation.Contract;
33 import org.apache.hc.core5.annotation.ThreadingBehavior;
34
35 /**
36 * Immutable, completed future.
37 *
38 * @param <T> the future result type of an asynchronous operation.
39 * @since 5.0
40 */
41 @Contract(threading = ThreadingBehavior.IMMUTABLE)
42 public class CompletedFuture<T> implements Future<T>, Cancellable {
43
44 private final T result;
45
46 public CompletedFuture(final T result) {
47 super();
48 this.result = result;
49 }
50
51 @Override
52 public boolean isCancelled() {
53 return false;
54 }
55
56 @Override
57 public boolean isDone() {
58 return true;
59 }
60
61 @Override
62 public T get() {
63 return this.result;
64 }
65
66 @Override
67 public T get(final long timeout, final TimeUnit unit) {
68 return this.result;
69 }
70
71 @Override
72 public boolean cancel(final boolean mayInterruptIfRunning) {
73 return false;
74 }
75
76 @Override
77 public boolean cancel() {
78 return false;
79 }
80
81 }