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1
7 package com.tirsen.nanning.definition;
8
9 import java.lang.reflect.Method  ;
10 import java.util.HashMap ;
11 import java.util.HashSet ;
12 import java.util.Map ;
13 import java.util.Set ;
14
15 import com.tirsen.nanning.*;
16
17
27 public class InterceptorDefinition {
28 private final Class interceptorClass;
29 private Interceptor singletonInterceptor;
30 private Map mapAttributes;
31 private Set negativeCache = new HashSet ();
32 private Set positiveCache = new HashSet ();
33
34 public InterceptorDefinition(Class interceptorClass) {
35 if (!Interceptor.class.isAssignableFrom(interceptorClass)) {
36 throw new IllegalArgumentException (interceptorClass + " is not an interceptor.");
37 }
38 this.interceptorClass = interceptorClass;
39 }
40
41 public Interceptor newInstance() {
42 if (singletonInterceptor != null) {
43 return singletonInterceptor;
44 }
45 try {
46 Interceptor instance = (Interceptor) interceptorClass.newInstance();
47 if (SingletonInterceptor.class.isAssignableFrom(interceptorClass)) {
48 singletonInterceptor = instance;
49 }
50
51 if (instance instanceof DefinitionAwareInterceptor) {
52 ((DefinitionAwareInterceptor) instance).setInterceptorDefinition(this);
53 }
54 return instance;
55 } catch (Exception e) {
56 throw new AspectException(e);
57 }
58 }
59
60 public Class getInterceptorClass() {
61 return interceptorClass;
62 }
63
64 public void setAttribute(String name, Object value) {
65 if (mapAttributes == null) mapAttributes = new HashMap ();
66 mapAttributes.put(name, value);
67 }
68
69 public Object getAttribute(String name) {
70 if (mapAttributes == null) {
71 return null;
72 } else {
73 return mapAttributes.get(name);
74 }
75 }
76
77 public boolean interceptsMethod(Method method) {
78 if (negativeCache.contains(method)) {
79 return false;
80 }
81 if (positiveCache.contains(method)) {
82 return true;
83 }
84
85 Interceptor interceptor = newInstance();
86 if (interceptor instanceof FilterMethodsInterceptor) {
87 if (((FilterMethodsInterceptor) interceptor).interceptsMethod(method)) {
88 positiveCache.add(method);
89 return true;
90 }
91 } else if (interceptor instanceof MethodInterceptor) {
92 positiveCache.add(method);
93 return true;
94 }
95 negativeCache.add(interceptor);
96 return false;
97 }
98
99 public boolean interceptsConstructor(Class interfaceClass) {
100 Interceptor interceptor = newInstance();
101 if (interceptor instanceof ConstructionInterceptor) {
102 return ((ConstructionInterceptor) interceptor).interceptsConstructor(interfaceClass);
103 }
104 return false;
105 }
106
107 public Interceptor getSingleton() {
108 if (singletonInterceptor == null) {
109 newInstance();
110 }
111 if (singletonInterceptor == null) {
112 throw new IllegalStateException ("This is not a singleton-interceptor: " + interceptorClass);
113 }
114
115 return singletonInterceptor;
116 }
117 }
118 |
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