1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
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7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
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11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
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19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24  */
25 
26 package jdk.jfr.consumer;
27 
28 import java.util.HashMap;
29 import java.util.Iterator;
30 
31 /**
32  * Commonly used data structure for looking up objects given an id (long value)
33  *
34  * TODO: Implement without using Map and Long objects, to minimize allocation
35  *
36  * @param <T>
37  */
38 final class LongMap<T> implements Iterable<T> {
39     private final HashMap<Long, T> map;
40 
LongMap()41     LongMap() {
42         map = new HashMap<>(101);
43     }
44 
put(long id, T object)45     void put(long id, T object) {
46         map.put(id, object);
47     }
48 
get(long id)49     T get(long id) {
50         return map.get(id);
51     }
52 
53     @Override
iterator()54     public Iterator<T> iterator() {
55         return map.values().iterator();
56     }
57 
keys()58     Iterator<Long> keys() {
59         return map.keySet().iterator();
60     }
61 }
62