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17 package com.sun.syndication.feed.impl;
18
19 import java.beans.IntrospectionException  ;
20 import java.beans.Introspector ;
21 import java.beans.PropertyDescriptor ;
22 import java.lang.reflect.Method ;
23 import java.lang.reflect.Modifier ;
24 import java.util.*;
25
26
34 public class BeanIntrospector {
35
36 private static final Map _introspected = new HashMap();
37
38 public static synchronized PropertyDescriptor [] getPropertyDescriptors(Class klass) throws IntrospectionException {
39 PropertyDescriptor [] descriptors = (PropertyDescriptor []) _introspected.get(klass);
40 if (descriptors==null) {
41 descriptors = getPDs(klass);
42 _introspected.put(klass,descriptors);
43 }
44 return descriptors;
45 }
46
47 private static PropertyDescriptor [] getPDs(Class klass) throws IntrospectionException {
48 Method [] methods = klass.getMethods();
49 Map getters = getPDs(methods,false);
50 Map setters = getPDs(methods,true);
51 List pds = merge(getters,setters);
52 PropertyDescriptor [] array = new PropertyDescriptor [pds.size()];
53 pds.toArray(array);
54 return array;
55 }
56
57 private static final String SETTER = "set";
58 private static final String GETTER = "get";
59 private static final String BOOLEAN_GETTER = "is";
60
61 private static Map getPDs(Method [] methods,boolean setters) throws IntrospectionException {
62 Map pds = new HashMap();
63 for (int i=0;i<methods.length;i++) {
64 String pName = null;
65 PropertyDescriptor pDescriptor = null;
66 if ((methods[i].getModifiers()&Modifier.PUBLIC)!=0) {
67 if (setters) {
68 if (methods[i].getName().startsWith(SETTER) &&
69 methods[i].getReturnType()==void.class && methods[i].getParameterTypes().length==1) {
70 pName = Introspector.decapitalize(methods[i].getName().substring(3));
71 pDescriptor = new PropertyDescriptor (pName,null,methods[i]);
72 }
73 }
74 else {
75 if (methods[i].getName().startsWith(GETTER) &&
76 methods[i].getReturnType()!=void.class && methods[i].getParameterTypes().length==0) {
77 pName = Introspector.decapitalize(methods[i].getName().substring(3));
78 pDescriptor = new PropertyDescriptor (pName,methods[i],null);
79 }
80 else
81 if (methods[i].getName().startsWith(BOOLEAN_GETTER) &&
82 methods[i].getReturnType()==boolean.class && methods[i].getParameterTypes().length==0) {
83 pName = Introspector.decapitalize(methods[i].getName().substring(2));
84 pDescriptor = new PropertyDescriptor (pName,methods[i],null);
85 }
86 }
87 }
88 if (pName!=null) {
89 pds.put(pName,pDescriptor);
90 }
91 }
92 return pds;
93 }
94
95 private static List merge(Map getters,Map setters) throws IntrospectionException {
96 List props = new ArrayList();
97 Set processedProps = new HashSet();
98 Iterator gs = getters.keySet().iterator();
99 while (gs.hasNext()) {
100 String name = (String ) gs.next();
101 PropertyDescriptor getter = (PropertyDescriptor ) getters.get(name);
102 PropertyDescriptor setter = (PropertyDescriptor ) setters.get(name);
103 if (setter!=null) {
104 processedProps.add(name);
105 PropertyDescriptor prop = new PropertyDescriptor (name,getter.getReadMethod(),setter.getWriteMethod());
106 props.add(prop);
107 }
108 else {
109 props.add(getter);
110 }
111 }
112 Set writeOnlyProps = new HashSet(setters.keySet());
113 writeOnlyProps.removeAll(processedProps);
114 Iterator ss = writeOnlyProps.iterator();
115 while (ss.hasNext()) {
116 String name = (String ) ss.next();
117 PropertyDescriptor setter = (PropertyDescriptor ) setters.get(name);
118 props.add(setter);
119 }
120 return props;
121 }
122
123 }
124 |
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