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comparison src/org/tmatesoft/hg/internal/Pool.java @ 195:c9b305df0b89

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author Artem Tikhomirov <tikhomirov.artem@gmail.com>
date Fri, 15 Apr 2011 05:17:44 +0200
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194:344e8d7e4d6e 195:c9b305df0b89
1 /*
2 * Copyright (c) 2011 TMate Software Ltd
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; version 2 of the License.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * For information on how to redistribute this software under
14 * the terms of a license other than GNU General Public License
15 * contact TMate Software at support@hg4j.com
16 */
17 package org.tmatesoft.hg.internal;
18
19 import java.util.HashMap;
20
21 /**
22 * Instance pooling.
23 *
24 * @author Artem Tikhomirov
25 * @author TMate Software Ltd.
26 */
27 public class Pool<T> {
28 private final HashMap<T,T> unify = new HashMap<T, T>();
29
30 public T unify(T t) {
31 T rv = unify.get(t);
32 if (rv == null) {
33 // first time we see a new value
34 unify.put(t, t);
35 rv = t;
36 }
37 return rv;
38 }
39 }