annotate src/goodjava/util/WeakCacheMap.java @ 1498:1b809d2fdf03

add CacheMap
author Franklin Schmidt <fschmidt@gmail.com>
date Fri, 08 May 2020 18:07:14 -0600
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1 package goodjava.util;
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2
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3 import java.lang.ref.ReferenceQueue;
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4 import java.lang.ref.WeakReference;
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5
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6
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7 public class WeakCacheMap<K,V> extends CacheMap<K,V> {
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8
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9 static final class MyWeakReference<K,V> extends WeakReference<V> implements MyReference<K,V> {
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10 private final K key;
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11
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12 MyWeakReference(K key,V value,ReferenceQueue<V> q) {
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13 super(value,q);
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14 this.key = key;
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15 }
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16
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17 public K key() {
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18 return key;
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19 }
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20
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21 public boolean equals(Object obj) {
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22 Object o = this.get();
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23 if( o==null )
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24 return false;
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25 WeakReference ref = (WeakReference)obj;
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26 return o.equals(ref.get());
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27 }
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28
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29 }
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30
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31 protected MyReference<K,V> newReference(K key,V value,ReferenceQueue<V> q) {
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32 return new MyWeakReference<K,V>(key,value,q);
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33 }
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34
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35 }