001 /*
002 * The FML Forge Mod Loader suite. Copyright (C) 2012 cpw
003 *
004 * This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free
005 * Software Foundation; either version 2.1 of the License, or any later version.
006 *
007 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
008 * A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
009 *
010 * You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51
011 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
012 */
013 package cpw.mods.fml.relauncher;
014
015 import java.lang.reflect.Field;
016 import java.lang.reflect.Method;
017 /**
018 * Some reflection helper code.
019 *
020 * @author cpw
021 *
022 */
023 public class ReflectionHelper
024 {
025 public static class UnableToFindMethodException extends RuntimeException
026 {
027 private String[] methodNames;
028
029 public UnableToFindMethodException(String[] methodNames, Exception failed)
030 {
031 super(failed);
032 this.methodNames = methodNames;
033 }
034
035 }
036
037 public static class UnableToFindClassException extends RuntimeException
038 {
039 private String[] classNames;
040
041 public UnableToFindClassException(String[] classNames, Exception err)
042 {
043 super(err);
044 this.classNames = classNames;
045 }
046
047 }
048
049 public static class UnableToAccessFieldException extends RuntimeException
050 {
051
052 private String[] fieldNameList;
053
054 public UnableToAccessFieldException(String[] fieldNames, Exception e)
055 {
056 super(e);
057 this.fieldNameList = fieldNames;
058 }
059 }
060
061 public static class UnableToFindFieldException extends RuntimeException
062 {
063 private String[] fieldNameList;
064 public UnableToFindFieldException(String[] fieldNameList, Exception e)
065 {
066 super(e);
067 this.fieldNameList = fieldNameList;
068 }
069 }
070
071 public static Field findField(Class<?> clazz, String... fieldNames)
072 {
073 Exception failed = null;
074 for (String fieldName : fieldNames)
075 {
076 try
077 {
078 Field f = clazz.getDeclaredField(fieldName);
079 f.setAccessible(true);
080 return f;
081 }
082 catch (Exception e)
083 {
084 failed = e;
085 }
086 }
087 throw new UnableToFindFieldException(fieldNames, failed);
088 }
089
090 @SuppressWarnings("unchecked")
091 public static <T, E> T getPrivateValue(Class <? super E > classToAccess, E instance, int fieldIndex)
092 {
093 try
094 {
095 Field f = classToAccess.getDeclaredFields()[fieldIndex];
096 f.setAccessible(true);
097 return (T) f.get(instance);
098 }
099 catch (Exception e)
100 {
101 throw new UnableToAccessFieldException(new String[0], e);
102 }
103 }
104
105 @SuppressWarnings("unchecked")
106 public static <T, E> T getPrivateValue(Class <? super E > classToAccess, E instance, String... fieldNames)
107 {
108 try
109 {
110 return (T) findField(classToAccess, fieldNames).get(instance);
111 }
112 catch (Exception e)
113 {
114 throw new UnableToAccessFieldException(fieldNames, e);
115 }
116 }
117
118 public static <T, E> void setPrivateValue(Class <? super T > classToAccess, T instance, E value, int fieldIndex)
119 {
120 try
121 {
122 Field f = classToAccess.getDeclaredFields()[fieldIndex];
123 f.setAccessible(true);
124 f.set(instance, value);
125 }
126 catch (Exception e)
127 {
128 throw new UnableToAccessFieldException(new String[0] , e);
129 }
130 }
131
132 public static <T, E> void setPrivateValue(Class <? super T > classToAccess, T instance, E value, String... fieldNames)
133 {
134 try
135 {
136 findField(classToAccess, fieldNames).set(instance, value);
137 }
138 catch (Exception e)
139 {
140 throw new UnableToAccessFieldException(fieldNames, e);
141 }
142 }
143
144 public static Class<? super Object> getClass(ClassLoader loader, String... classNames)
145 {
146 Exception err = null;
147 for (String className : classNames)
148 {
149 try
150 {
151 return (Class<? super Object>) Class.forName(className, false, loader);
152 }
153 catch (Exception e)
154 {
155 err = e;
156 }
157 }
158
159 throw new UnableToFindClassException(classNames, err);
160 }
161
162
163 public static <E> Method findMethod(Class<? super E> clazz, E instance, String[] methodNames, Class<?>... methodTypes)
164 {
165 Exception failed = null;
166 for (String methodName : methodNames)
167 {
168 try
169 {
170 Method m = clazz.getDeclaredMethod(methodName, methodTypes);
171 m.setAccessible(true);
172 return m;
173 }
174 catch (Exception e)
175 {
176 failed = e;
177 }
178 }
179 throw new UnableToFindMethodException(methodNames, failed);
180 }
181 }