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1
7
8 package org.dom4j.bean;
9
10 import java.beans.BeanInfo  ;
11 import java.beans.IntrospectionException ;
12 import java.beans.Introspector ;
13 import java.beans.PropertyDescriptor ;
14 import java.lang.reflect.Method ;
15 import java.util.HashMap ;
16 import java.util.Map ;
17
18 import org.dom4j.DocumentFactory;
19 import org.dom4j.QName;
20
21
29 public class BeanMetaData {
30
31 protected static final Object [] NULL_ARGS = {};
32
33
34 private static Map singletonCache = new HashMap ();
35
36 private static final DocumentFactory DOCUMENT_FACTORY = BeanDocumentFactory
37 .getInstance();
38
39
40 private Class beanClass;
41
42
43 private PropertyDescriptor [] propertyDescriptors;
44
45
46 private QName[] qNames;
47
48
49 private Method [] readMethods;
50
51
52 private Method [] writeMethods;
53
54
55 private Map nameMap = new HashMap ();
56
57 public BeanMetaData(Class beanClass) {
58 this.beanClass = beanClass;
59
60 if (beanClass != null) {
61 try {
62 BeanInfo beanInfo = Introspector.getBeanInfo(beanClass);
63 propertyDescriptors = beanInfo.getPropertyDescriptors();
64 } catch (IntrospectionException e) {
65 handleException(e);
66 }
67 }
68
69 if (propertyDescriptors == null) {
70 propertyDescriptors = new PropertyDescriptor [0];
71 }
72
73 int size = propertyDescriptors.length;
74 qNames = new QName[size];
75 readMethods = new Method [size];
76 writeMethods = new Method [size];
77
78 for (int i = 0; i < size; i++) {
79 PropertyDescriptor propertyDescriptor = propertyDescriptors[i];
80 String name = propertyDescriptor.getName();
81 QName qName = DOCUMENT_FACTORY.createQName(name);
82 qNames[i] = qName;
83 readMethods[i] = propertyDescriptor.getReadMethod();
84 writeMethods[i] = propertyDescriptor.getWriteMethod();
85
86 Integer index = new Integer (i);
87 nameMap.put(name, index);
88 nameMap.put(qName, index);
89 }
90 }
91
92
100 public static BeanMetaData get(Class beanClass) {
101 BeanMetaData answer = (BeanMetaData) singletonCache.get(beanClass);
102
103 if (answer == null) {
104 answer = new BeanMetaData(beanClass);
105 singletonCache.put(beanClass, answer);
106 }
107
108 return answer;
109 }
110
111
116 public int attributeCount() {
117 return propertyDescriptors.length;
118 }
119
120 public BeanAttributeList createAttributeList(BeanElement parent) {
121 return new BeanAttributeList(parent, this);
122 }
123
124 public QName getQName(int index) {
125 return qNames[index];
126 }
127
128 public int getIndex(String name) {
129 Integer index = (Integer ) nameMap.get(name);
130
131 return (index != null) ? index.intValue() : (-1);
132 }
133
134 public int getIndex(QName qName) {
135 Integer index = (Integer ) nameMap.get(qName);
136
137 return (index != null) ? index.intValue() : (-1);
138 }
139
140 public Object getData(int index, Object bean) {
141 try {
142 Method method = readMethods[index];
143
144 return method.invoke(bean, NULL_ARGS);
145 } catch (Exception e) {
146 handleException(e);
147
148 return null;
149 }
150 }
151
152 public void setData(int index, Object bean, Object data) {
153 try {
154 Method method = writeMethods[index];
155 Object [] args = {data};
156 method.invoke(bean, args);
157 } catch (Exception e) {
158 handleException(e);
159 }
160 }
161
162 protected void handleException(Exception e) {
165 }
167 }
168
169
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