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1
50 package net.sf.just4log.transform;
51
52 import java.util.HashMap  ;
53
54 import org.apache.bcel.Constants;
55 import org.apache.bcel.generic.ConstantPoolGen;
56 import org.apache.bcel.generic.IFEQ;
57 import org.apache.bcel.generic.InstructionHandle;
58 import org.apache.bcel.generic.InstructionList;
59 import org.apache.bcel.generic.InvokeInstruction;
60 import org.apache.bcel.generic.MethodGen;
61 import org.apache.bcel.generic.ObjectType;
62 import org.apache.bcel.generic.PUSH;
63 import org.apache.bcel.generic.Type;
64 import org.apache.commons.logging.Log;
65 import org.apache.commons.logging.LogFactory;
66
67
70
71 public class Log4jTransform extends Transform {
72
73 private static final String INTERFACE = "org.apache.log4j.Logger";
74
77 private static final ObjectType logType = new ObjectType(INTERFACE);
78 public ObjectType getLogType() {
79
80 return logType;
81 }
82 private static final String LEVEL = "org.apache.log4j.Level";
83 private static final String PRIORITY = "org.apache.log4j.Priority";
84 private static final ObjectType LevelType = new ObjectType(LEVEL);
85 private static final ObjectType[] ARGUMENTS_ISENABLEDFOR =
86 new ObjectType[] { new ObjectType(PRIORITY)};
87
88 private static Log logger = LogFactory.getLog(Log4jTransform.class);
89 private static String CLASSID =
90 "$Id: Log4jTransform.java,v 1.8 2003/07/22 23:38:37 lbruand Exp $";
91
92 public static void register() {
93 Transform.register(new Log4jTransform());
94 }
95
96
99 public Log4jTransform() {
100 super();
101 }
102
103
106 public InstructionHandle insertFork(
107 InstructionList il,
108 InstructionHandle getStaticHandle,
109 InstructionHandle invokeHandle,
110 ConstantPoolGen cp) {
111 String level =
112 getIsEnabled(
113 ((InvokeInstruction) invokeHandle.getInstruction()),
114 cp);
115 if (level == null) {
116 return null;
118 }
119 logger.info("the level of enabling is: " + level);
120 logger.info("Inserting GETSTATIC");
121 InstructionHandle insertHandle =
122 il.insert(getStaticHandle, getStaticHandle.getInstruction().copy());
123 il.insert(
124 getStaticHandle,
125 instFact.createGetStatic(LEVEL, level, LevelType));
126
127 logger.info("Inserting INVOKE call to isEnabledFor");
128
129 il.insert(
130 getStaticHandle,
131 instFact.createInvoke(
132 INTERFACE,
133 "isEnabledFor",
134 Type.BOOLEAN,
135 ARGUMENTS_ISENABLEDFOR,
136 Constants.INVOKEVIRTUAL));
137 logger.info("Inserting IFEQ");
138 il.insert(getStaticHandle, new IFEQ(invokeHandle.getNext()));
139 return insertHandle;
140 }
141 private static HashMap mapping = new HashMap ();
142 static {
143 mapping.put("debug", "DEBUG");
144 mapping.put("error", "ERROR");
145 mapping.put("fatal", "FATAL");
146 mapping.put("info", "INFO");
147 mapping.put("warn", "WARN");
148 }
149 public String getIsEnabled(
150 InvokeInstruction invokeInstruction,
151 ConstantPoolGen cp) {
152 return (String ) mapping.get(invokeInstruction.getMethodName(cp));
153 }
154
155
158 public String getClassname() {
159 return INTERFACE;
160 }
161
162
165 public InstructionHandle insertEnter(
166 MethodGen orig,
167 InstructionList il,
168 InstructionHandle firstInstructionHandle,
169 ConstantPoolGen cp) {
170 logger.info("Inserting Enter code.");
171 InstructionHandle backup = il.insert(
172 firstInstructionHandle,
173 instFact.createGetStatic(
174 clazz.getClassName(),
175 loggerAttribute.getName(),
176 loggerAttribute.getType()));
177
178 il.insert(firstInstructionHandle,
179 new PUSH(cp, Transform.ENTER_STRING+ getMethodRepr(orig))
180 );
181
182
183 il.insert(
184 firstInstructionHandle,
185 instFact.createInvoke(
186 INTERFACE,
187 "debug",
188 Type.VOID,
189 new Type[] {Type.OBJECT},
190 Constants.INVOKEVIRTUAL));
191
192 return backup;
193
194 }
195
196
199 public InstructionHandle insertExit(
200 MethodGen orig,
201 InstructionList il,
202 InstructionHandle returnInstructionHandle,
203 ConstantPoolGen cp) {
204 logger.info("Inserting Exit code.");
205 InstructionHandle backup = il.insert(
206 returnInstructionHandle,
207 instFact.createGetStatic(
208 clazz.getClassName(),
209 loggerAttribute.getName(),
210 loggerAttribute.getType()));
211
212 il.insert(returnInstructionHandle,
213 new PUSH(cp, Transform.EXIT_STRING+ getMethodRepr(orig))
214 );
215
216
217 il.insert(
218 returnInstructionHandle,
219 instFact.createInvoke(
220 INTERFACE,
221 "debug",
222 Type.VOID,
223 new Type[] {Type.OBJECT},
224 Constants.INVOKEVIRTUAL));
225
226 return backup;
227
228 }
229
230 }
231 |
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