1 /*
2 * Licensed under the Apache License, Version 2.0 (the "License");
3 * you may not use this file except in compliance with the License.
4 * You may obtain a copy of the License at
5 *
6 * http://www.apache.org/licenses/LICENSE-2.0
7 *
8 * Unless required by applicable law or agreed to in writing, software
9 * distributed under the License is distributed on an "AS IS" BASIS,
10 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11 * See the License for the specific language governing permissions and
12 * limitations under the License.
13 *
14 */
15 package org.esigate.parser.future;
16
17 import java.util.concurrent.Future;
18 import java.util.concurrent.TimeUnit;
19
20 /**
21 * This class is a simple wrapper on a CharSequence.
22 * <p>
23 * This Future object already has it result and does not use any background Thread and simply return the
24 * {@link CharSequence} provided at the construction time.
25 *
26 * @author Nicolas Richeton
27 *
28 */
29 public class CharSequenceFuture implements Future<CharSequence> {
30 private final CharSequence seq;
31
32 /**
33 * Create a new Future object which will return the {@link CharSequence} provided as parameter.
34 *
35 * @param charSequence
36 * the sequence which will be returned on {@link #get()}
37 */
38 public CharSequenceFuture(CharSequence charSequence) {
39 this.seq = charSequence;
40 }
41
42 /*
43 * (non-Javadoc)
44 *
45 * @see java.util.concurrent.Future#isDone()
46 */
47 @Override
48 public boolean isDone() {
49 // This future is already done per implementation.
50 return true;
51 }
52
53 /*
54 * (non-Javadoc)
55 *
56 * @see java.util.concurrent.Future#isCancelled()
57 */
58 @Override
59 public boolean isCancelled() {
60 // Cannot ever been cancelled
61 return false;
62 }
63
64 /*
65 * (non-Javadoc)
66 *
67 * @see java.util.concurrent.Future#get(long, java.util.concurrent.TimeUnit)
68 */
69 @Override
70 public CharSequence get(long timeout, TimeUnit unit) {
71 // Get will never block, just use the default implementation.
72 return get();
73 }
74
75 /*
76 * (non-Javadoc)
77 *
78 * @see java.util.concurrent.Future#get()
79 */
80 @Override
81 public CharSequence get() {
82 // Return the wrapped CharSequence.
83 return this.seq;
84 }
85
86 /*
87 * (non-Javadoc)
88 *
89 * @see java.util.concurrent.Future#cancel(boolean)
90 */
91 @Override
92 public boolean cancel(boolean mayInterruptIfRunning) {
93 // Cannot be cancelled.
94 return false;
95 }
96 }