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1
22
23 package org.jboss.aop.util.reference;
24
25 import java.lang.ref.Reference  ;
26 import java.lang.ref.SoftReference ;
27 import java.lang.ref.WeakReference ;
28
29
38 public abstract class PersistentReference
39 {
40 public static final int REFERENCE_WEAK=1;
41 public static final int REFERENCE_SOFT=2;
42
43 private WeakReference classReference;
44 private Reference referencedObject;
45 private int referenceType=0;
46
47
53 public PersistentReference(Class clazz, Object referencedObject, int referenceType)
54 {
55 this.referenceType=referenceType;
56 if (clazz!=null)
57 {
58 classReference = new WeakReference (clazz);
59 }
60 buildReference(referencedObject);
61 }
62
63
64 protected Object internalGet()
65 {
66 if (referencedObject==null)
67 return null;
68
69 return referencedObject.get();
70
71
72 }
73
74 public Object get()
75 {
76 if (referencedObject==null)
77 return null;
78
79 Object returnValue = referencedObject.get();
80 if (returnValue==null)
81 {
82 try
83 {
84 return rebuildReference();
86 }
87 catch (Exception e)
88 {
89 throw new RuntimeException (e.getMessage(),e);
90 }
91 }
92
93 return returnValue;
94 }
95
96 public abstract Object rebuildReference() throws Exception ;
97 public void buildReference(Object obj)
98 {
99 if (obj==null)
100 {
101 referencedObject = null;
102 }
103 else
104 {
105 if (referenceType==REFERENCE_WEAK)
106 {
107 referencedObject = new WeakReference (obj);
108 }
109 else
110 {
111 referencedObject = new SoftReference (obj);
112 }
113 }
114 }
115
116 public Class getMappedClass()
117 {
118 if (classReference==null) return null;
119 Class returnClass = (Class )classReference.get();
120 if (returnClass==null)
121 {
122 throw new RuntimeException ("Class was already unloaded");
123 }
124 return (Class )returnClass;
125 }
126
127 }
128 |
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