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1
22 package org.jboss.reflect.plugins.introspection;
23
24 import java.lang.reflect.Constructor  ;
25 import java.lang.reflect.Field ;
26 import java.lang.reflect.InvocationTargetException ;
27 import java.lang.reflect.Method ;
28 import java.util.ArrayList ;
29
30 import org.jboss.util.Strings;
31
32
38 public class ReflectionUtils
39 {
40
49 public static Object invoke(Method method, Object target, Object [] arguments) throws Throwable
50 {
51 if (method == null)
52 throw new IllegalArgumentException ("Null method");
53 try
54 {
55 return method.invoke(target, arguments);
56 }
57 catch (Throwable t)
58 {
59 throw handleErrors(method.getName(), Strings.defaultToString(target), method.getParameterTypes(), arguments, t);
60 }
61 }
62
63
70 public static Object newInstance(Class clazz) throws Throwable
71 {
72 if (clazz == null)
73 throw new IllegalArgumentException ("Null clazz");
74 try
75 {
76 return clazz.newInstance();
77 }
78 catch (Throwable t)
79 {
80 throw handleErrors("new", clazz.getName(), null, null, t);
81 }
82 }
83
84
92 public static Object newInstance(String className, ClassLoader cl) throws Throwable
93 {
94 if (className == null)
95 throw new IllegalArgumentException ("Null class name");
96 if (cl == null)
97 throw new IllegalArgumentException ("Null classloader");
98 Class clazz = cl.loadClass(className);
99 try
100 {
101 return clazz.newInstance();
102 }
103 catch (Throwable t)
104 {
105 throw handleErrors("new", clazz.getName(), null, null, t);
106 }
107 }
108
109
116 public static Object newInstance(String className) throws Throwable
117 {
118 ClassLoader cl = Thread.currentThread().getContextClassLoader();
119 return newInstance(className, cl);
120 }
121
122
130 public static Object newInstance(Constructor constructor, Object [] arguments) throws Throwable
131 {
132 if (constructor == null)
133 throw new IllegalArgumentException ("Null constructor");
134 try
135 {
136 return constructor.newInstance(arguments);
137 }
138 catch (Throwable t)
139 {
140 throw handleErrors("new", constructor.getClass().getName(), constructor.getParameterTypes(), arguments, t);
141 }
142 }
143
144
152 public static Object getField(Field field, Object target) throws Throwable
153 {
154 if (field == null)
155 throw new IllegalArgumentException ("Null field");
156 try
157 {
158 return field.get(target);
159 }
160 catch (Throwable t)
161 {
162 throw handleErrors("set", field, target, null, t);
163 }
164 }
165
166
175 public static Object setField(Field field, Object target, Object value) throws Throwable
176 {
177 if (field == null)
178 throw new IllegalArgumentException ("Null field");
179 try
180 {
181 field.set(target, value);
182 return null;
183 }
184 catch (Throwable t)
185 {
186 throw handleErrors("set", field, target, value, t);
187 }
188 }
189
190
201 public static Throwable handleErrors(String context, Object target, Class [] parameters, Object [] arguments, Throwable t) throws Throwable
202 {
203 if (t instanceof IllegalArgumentException )
204 {
205 if (target == null)
206 throw new IllegalArgumentException ("Null target for " + context);
207 ArrayList <String > expected = new ArrayList <String >();
208 if (parameters != null)
209 {
210 for (int i = 0; i < parameters.length; ++i)
211 expected.add(parameters[i].getName());
212 }
213 ArrayList <String > actual = new ArrayList <String >();
214 if (arguments != null)
215 {
216 for (int i = 0; i < arguments.length; ++i)
217 {
218 if (arguments[i] == null)
219 actual.add(null);
220 else
221 actual.add(arguments[i].getClass().getName());
222 }
223 }
224 throw new IllegalArgumentException ("Wrong arguments. " + context + " for target " + target + " expected=" + expected + " actual=" + actual);
225 }
226 else if (t instanceof InvocationTargetException )
227 {
228 throw ((InvocationTargetException ) t).getTargetException();
229 }
230 throw t;
231 }
232
233
244 public static Throwable handleErrors(String context, Field field, Object target, Object value, Throwable t) throws Throwable
245 {
246 if (t instanceof IllegalArgumentException )
247 {
248 String valueType = null;
249 if (value != null)
250 valueType = value.getClass().getName();
251 throw new IllegalArgumentException ("Error invoking field " + context + " for target " + target + " field " + field.getName() + " expected=" + field.getType().getName() + " actual=" + valueType);
252 }
253 throw t;
254 }
255 }
256 |
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