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1
17 package org.apache.el.util;
18
19 import java.beans.IntrospectionException  ;
20 import java.beans.Introspector ;
21 import java.beans.PropertyDescriptor ;
22 import java.lang.reflect.Array ;
23 import java.lang.reflect.Method ;
24 import java.util.Arrays ;
25
26 import javax.el.ELException;
27 import javax.el.MethodNotFoundException;
28 import javax.el.PropertyNotFoundException;
29
30 import org.apache.el.lang.ELSupport;
31
32
33
39 public class ReflectionUtil {
40
41 protected static final String [] EMPTY_STRING = new String [0];
42
43 protected static final String [] PRIMITIVE_NAMES = new String [] { "boolean",
44 "byte", "char", "double", "float", "int", "long", "short", "void" };
45
46 protected static final Class [] PRIMITIVES = new Class [] { boolean.class,
47 byte.class, char.class, double.class, float.class, int.class,
48 long.class, short.class, Void.TYPE };
49
50
53 private ReflectionUtil() {
54 super();
55 }
56
57 public static Class forName(String name) throws ClassNotFoundException {
58 if (null == name || "".equals(name)) {
59 return null;
60 }
61 Class c = forNamePrimitive(name);
62 if (c == null) {
63 if (name.endsWith("[]")) {
64 String nc = name.substring(0, name.length() - 2);
65 c = Class.forName(nc, true, Thread.currentThread().getContextClassLoader());
66 c = Array.newInstance(c, 0).getClass();
67 } else {
68 c = Class.forName(name, true, Thread.currentThread().getContextClassLoader());
69 }
70 }
71 return c;
72 }
73
74 protected static Class forNamePrimitive(String name) {
75 if (name.length() <= 8) {
76 int p = Arrays.binarySearch(PRIMITIVE_NAMES, name);
77 if (p >= 0) {
78 return PRIMITIVES[p];
79 }
80 }
81 return null;
82 }
83
84
90 public static Class [] toTypeArray(String [] s) throws ClassNotFoundException {
91 if (s == null)
92 return null;
93 Class [] c = new Class [s.length];
94 for (int i = 0; i < s.length; i++) {
95 c[i] = forName(s[i]);
96 }
97 return c;
98 }
99
100
105 public static String [] toTypeNameArray(Class [] c) {
106 if (c == null)
107 return null;
108 String [] s = new String [c.length];
109 for (int i = 0; i < c.length; i++) {
110 s[i] = c[i].getName();
111 }
112 return s;
113 }
114
115
123 public static Method getMethod(Object base, Object property,
124 Class [] paramTypes) throws MethodNotFoundException {
125 if (base == null || property == null) {
126 throw new MethodNotFoundException(MessageFactory.get(
127 "error.method.notfound", base, property,
128 paramString(paramTypes)));
129 }
130
131 String methodName = (property instanceof String ) ? (String ) property
132 : property.toString();
133
134 Method method = null;
135 try {
136 method = base.getClass().getMethod(methodName, paramTypes);
137 } catch (NoSuchMethodException nsme) {
138 throw new MethodNotFoundException(MessageFactory.get(
139 "error.method.notfound", base, property,
140 paramString(paramTypes)));
141 }
142 return method;
143 }
144
145 protected static final String paramString(Class [] types) {
146 if (types != null) {
147 StringBuffer sb = new StringBuffer ();
148 for (int i = 0; i < types.length; i++) {
149 sb.append(types[i].getName()).append(", ");
150 }
151 if (sb.length() > 2) {
152 sb.setLength(sb.length() - 2);
153 }
154 return sb.toString();
155 }
156 return null;
157 }
158
159
166 public static PropertyDescriptor getPropertyDescriptor(Object base,
167 Object property) throws ELException, PropertyNotFoundException {
168 String name = ELSupport.coerceToString(property);
169 PropertyDescriptor p = null;
170 try {
171 PropertyDescriptor [] desc = Introspector.getBeanInfo(
172 base.getClass()).getPropertyDescriptors();
173 for (int i = 0; i < desc.length; i++) {
174 if (desc[i].getName().equals(name)) {
175 return desc[i];
176 }
177 }
178 } catch (IntrospectionException ie) {
179 throw new ELException(ie);
180 }
181 throw new PropertyNotFoundException(MessageFactory.get(
182 "error.property.notfound", base, name));
183 }
184 }
185 |
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