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Java > Open Source Codes > org > logicalcobwebs > cglib > proxy > CallbackFilter


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54 package org.logicalcobwebs.cglib.proxy;
55
56 import java.lang.reflect.Method JavaDoc;
57
58 /**
59  * Map methods of subclasses generated by {@link Enhancer} to a particular
60  * callback. The type of the callbacks chosen for each method affects
61  * the bytecode generated for that method in the subclass, and cannot
62  * change for the life of the class.
63  */
64 public interface CallbackFilter {
65     static final CallbackFilter ALL_ZERO = new CallbackFilter() {
66         public int accept(Method JavaDoc method) {
67             return 0;
68         }
69         public String JavaDoc toString() {
70             return "ALL_ZERO";
71         }
72         public int hashCode() {
73             return 999;
74         }
75     };
76     
77     /**
78      * Map a method to a callback.
79      * @param method the intercepted method
80      * @return the index into the array of callbacks (as specified by {@link Enhancer#setCallbacks}) to use for the method,
81      */
82     int accept(Method JavaDoc method);
83
84     /**
85      * The <code>CallbackFilter</code> in use affects which cached class
86      * the <code>Enhancer</code> will use, so this is a reminder that
87      * you should correctly implement <code>equals</code> and
88      * <code>hashCode</code> for custom <code>CallbackFilter</code>
89      * implementations in order to improve performance.
90     */
91     boolean equals(Object JavaDoc o);
92 }
93
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