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1 package org.python.core;
2
3 import java.lang.ref.WeakReference  ;
4 import java.lang.ref.ReferenceQueue ;
5 import java.util.HashMap ;
6
7 public class IdImpl2 extends IdImpl {
8
9 public static class WeakIdentityMap {
10
11 private ReferenceQueue refqueue = new ReferenceQueue ();
12 private HashMap hashmap = new HashMap ();
13
14 private void cleanup() {
15 Object k;
16 while ((k = refqueue.poll()) != null) {
17 hashmap.remove(k);
18 }
19 }
20
21 private class WeakIdKey extends WeakReference {
22 private int hashcode;
23
24 WeakIdKey(Object obj) {
25 super(obj,refqueue);
26 hashcode = System.identityHashCode(obj);
27 }
28
29 public int hashCode() {
30 return hashcode;
31 }
32
33 public boolean equals(Object other) {
34 Object obj = this.get();
35 if (obj != null) {
36 return obj == ((WeakIdKey)other).get();
37 } else {
38 return this == other;
39 }
40 }
41 }
42
43 public int _internal_map_size() {
44 return hashmap.size();
45 }
46
47 public void put(Object key,Object val) {
48 cleanup();
49 hashmap.put(new WeakIdKey(key),val);
50 }
51
52 public Object get(Object key) {
53 cleanup();
54 return hashmap.get(new WeakIdKey(key));
55 }
56
57 public void remove(Object key) {
58 cleanup();
59 hashmap.remove(new WeakIdKey(key));
60 }
61
62 }
63
64 private WeakIdentityMap id_map = new WeakIdentityMap();
65 private long sequential_id = 0;
66
67 public long id(PyObject o) {
68 if (o instanceof PyJavaInstance) {
69 return java_obj_id(((PyJavaInstance)o).javaProxy);
70 } else {
71 return java_obj_id(o);
72 }
73 }
74
75 public String idstr(PyObject o) {
78 return Long.toString(id(o));
79 }
80
81 public synchronized long java_obj_id(Object o) {
82 Long cand = (Long )id_map.get(o);
83 if (cand == null) {
84 sequential_id++;
85 long new_id = sequential_id;
86 id_map.put(o,new Long (new_id));
87 return new_id;
88 }
89 return cand.longValue();
90 }
91
92 }
93 |
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