1
2
3
4
5
6
7
8
9
10
11
12
13
14 package org.eclipse.jetty.util;
15
16 import java.lang.reflect.Field;
17 import java.lang.reflect.Member;
18 import java.lang.reflect.Method;
19 import java.lang.reflect.Modifier;
20 import java.util.Arrays;
21 import java.util.List;
22
23
24
25
26
27
28 public class IntrospectionUtil
29 {
30
31 public static boolean isJavaBeanCompliantSetter (Method method)
32 {
33 if (method == null)
34 return false;
35
36 if (method.getReturnType() != Void.TYPE)
37 return false;
38
39 if (!method.getName().startsWith("set"))
40 return false;
41
42 if (method.getParameterTypes().length != 1)
43 return false;
44
45 return true;
46 }
47
48 public static Method findMethod (Class<?> clazz, String methodName, Class<?>[] args, boolean checkInheritance, boolean strictArgs)
49 throws NoSuchMethodException
50 {
51 if (clazz == null)
52 throw new NoSuchMethodException("No class");
53 if (methodName==null || methodName.trim().equals(""))
54 throw new NoSuchMethodException("No method name");
55
56 Method method = null;
57 Method[] methods = clazz.getDeclaredMethods();
58 for (int i=0;i<methods.length && method==null;i++)
59 {
60 if (methods[i].getName().equals(methodName) && checkParams(methods[i].getParameterTypes(), (args==null?new Class[] {}:args), strictArgs))
61 {
62 method = methods[i];
63 }
64
65 }
66 if (method!=null)
67 {
68 return method;
69 }
70 else if (checkInheritance)
71 return findInheritedMethod(clazz.getPackage(), clazz.getSuperclass(), methodName, args, strictArgs);
72 else
73 throw new NoSuchMethodException("No such method "+methodName+" on class "+clazz.getName());
74
75 }
76
77
78
79
80
81 public static Field findField (Class<?> clazz, String targetName, Class<?> targetType, boolean checkInheritance, boolean strictType)
82 throws NoSuchFieldException
83 {
84 if (clazz == null)
85 throw new NoSuchFieldException("No class");
86 if (targetName==null)
87 throw new NoSuchFieldException("No field name");
88
89 try
90 {
91 Field field = clazz.getDeclaredField(targetName);
92 if (strictType)
93 {
94 if (field.getType().equals(targetType))
95 return field;
96 }
97 else
98 {
99 if (field.getType().isAssignableFrom(targetType))
100 return field;
101 }
102 if (checkInheritance)
103 {
104 return findInheritedField(clazz.getPackage(), clazz.getSuperclass(), targetName, targetType, strictType);
105 }
106 else
107 throw new NoSuchFieldException("No field with name "+targetName+" in class "+clazz.getName()+" of type "+targetType);
108 }
109 catch (NoSuchFieldException e)
110 {
111 return findInheritedField(clazz.getPackage(),clazz.getSuperclass(), targetName,targetType,strictType);
112 }
113 }
114
115
116
117
118
119 public static boolean isInheritable (Package pack, Member member)
120 {
121 if (pack==null)
122 return false;
123 if (member==null)
124 return false;
125
126 int modifiers = member.getModifiers();
127 if (Modifier.isPublic(modifiers))
128 return true;
129 if (Modifier.isProtected(modifiers))
130 return true;
131 if (!Modifier.isPrivate(modifiers) && pack.equals(member.getDeclaringClass().getPackage()))
132 return true;
133
134 return false;
135 }
136
137
138
139
140 public static boolean checkParams (Class<?>[] formalParams, Class<?>[] actualParams, boolean strict)
141 {
142 if (formalParams==null)
143 return actualParams==null;
144 if (actualParams==null)
145 return false;
146
147 if (formalParams.length!=actualParams.length)
148 return false;
149
150 if (formalParams.length==0)
151 return true;
152
153 int j=0;
154 if (strict)
155 {
156 while (j<formalParams.length && formalParams[j].equals(actualParams[j]))
157 j++;
158 }
159 else
160 {
161 while ((j<formalParams.length) && (formalParams[j].isAssignableFrom(actualParams[j])))
162 {
163 j++;
164 }
165 }
166
167 if (j!=formalParams.length)
168 {
169 return false;
170 }
171
172 return true;
173 }
174
175
176 public static boolean isSameSignature (Method methodA, Method methodB)
177 {
178 if (methodA==null)
179 return false;
180 if (methodB==null)
181 return false;
182
183 List<Class<?>> parameterTypesA = Arrays.asList(methodA.getParameterTypes());
184 List<Class<?>> parameterTypesB = Arrays.asList(methodB.getParameterTypes());
185
186 if (methodA.getName().equals(methodB.getName())
187 &&
188 parameterTypesA.containsAll(parameterTypesB))
189 return true;
190
191 return false;
192 }
193
194 public static boolean isTypeCompatible (Class<?> formalType, Class<?> actualType, boolean strict)
195 {
196 if (formalType==null)
197 return actualType==null;
198 if (actualType==null)
199 return false;
200
201 if (strict)
202 return formalType.equals(actualType);
203 else
204 return formalType.isAssignableFrom(actualType);
205 }
206
207
208
209
210 public static boolean containsSameMethodSignature (Method method, Class<?> c, boolean checkPackage)
211 {
212 if (checkPackage)
213 {
214 if (!c.getPackage().equals(method.getDeclaringClass().getPackage()))
215 return false;
216 }
217
218 boolean samesig = false;
219 Method[] methods = c.getDeclaredMethods();
220 for (int i=0; i<methods.length && !samesig; i++)
221 {
222 if (IntrospectionUtil.isSameSignature(method, methods[i]))
223 samesig = true;
224 }
225 return samesig;
226 }
227
228
229 public static boolean containsSameFieldName(Field field, Class<?> c, boolean checkPackage)
230 {
231 if (checkPackage)
232 {
233 if (!c.getPackage().equals(field.getDeclaringClass().getPackage()))
234 return false;
235 }
236
237 boolean sameName = false;
238 Field[] fields = c.getDeclaredFields();
239 for (int i=0;i<fields.length && !sameName; i++)
240 {
241 if (fields[i].getName().equals(field.getName()))
242 sameName = true;
243 }
244 return sameName;
245 }
246
247
248
249 protected static Method findInheritedMethod (Package pack, Class<?> clazz, String methodName, Class<?>[] args, boolean strictArgs)
250 throws NoSuchMethodException
251 {
252 if (clazz==null)
253 throw new NoSuchMethodException("No class");
254 if (methodName==null)
255 throw new NoSuchMethodException("No method name");
256
257 Method method = null;
258 Method[] methods = clazz.getDeclaredMethods();
259 for (int i=0;i<methods.length && method==null;i++)
260 {
261 if (methods[i].getName().equals(methodName)
262 && isInheritable(pack,methods[i])
263 && checkParams(methods[i].getParameterTypes(), args, strictArgs))
264 method = methods[i];
265 }
266 if (method!=null)
267 {
268 return method;
269 }
270 else
271 return findInheritedMethod(clazz.getPackage(), clazz.getSuperclass(), methodName, args, strictArgs);
272 }
273
274 protected static Field findInheritedField (Package pack, Class<?> clazz, String fieldName, Class<?> fieldType, boolean strictType)
275 throws NoSuchFieldException
276 {
277 if (clazz==null)
278 throw new NoSuchFieldException ("No class");
279 if (fieldName==null)
280 throw new NoSuchFieldException ("No field name");
281 try
282 {
283 Field field = clazz.getDeclaredField(fieldName);
284 if (isInheritable(pack, field) && isTypeCompatible(fieldType, field.getType(), strictType))
285 return field;
286 else
287 return findInheritedField(clazz.getPackage(), clazz.getSuperclass(),fieldName, fieldType, strictType);
288 }
289 catch (NoSuchFieldException e)
290 {
291 return findInheritedField(clazz.getPackage(), clazz.getSuperclass(),fieldName, fieldType, strictType);
292 }
293 }
294
295 }