@Override
protected void onApply(CtBehavior behavior, Bytecode bytecode) throws BadBytecode {
bytecode = BytecodeTools.prepareMethodForBytecode(behavior, bytecode);
// loop through the opcodes and change any GT/GE opcodes to ICMPGT/ICMPGE
CodeIterator iterator = behavior.getMethodInfo().getCodeAttribute().iterator();
while (iterator.hasNext()) {
int index = iterator.next();
int opcode = iterator.byteAt(index);
switch (opcode) {
case Opcode.IFGT:
// overwrite the opcode
iterator.writeByte(Opcode.IF_ICMPGT, index);
// insert the method call
iterator.insertAt(index, bytecode.get());
behavior.getMethodInfo().getCodeAttribute().computeMaxStack();
break;
case Opcode.IFGE:
// overwrite the opcode
iterator.writeByte(Opcode.IF_ICMPGE, index);
// insert the method call
iterator.insertAt(index, bytecode.get());
behavior.getMethodInfo().getCodeAttribute().computeMaxStack();
break;
}
}
}
/**
* Return javaassist source snippet which lists all the parameters and their values. If available
* the source names are extracted from the debug information and used, otherwise just a number is
* shown.
*
* @param method
* @return
* @throws NotFoundException
*/
public static String getSignature(CtBehavior method) throws NotFoundException {
CtClass[] parameterTypes = method.getParameterTypes();
CodeAttribute codeAttribute = method.getMethodInfo().getCodeAttribute();
LocalVariableAttribute locals = null;
if (codeAttribute != null) {
AttributeInfo attribute;
attribute = codeAttribute.getAttribute("LocalVariableTable");
locals = (LocalVariableAttribute) attribute;
}
String methodName = method.getName();
StringBuilder sb = new StringBuilder(methodName).append("(\" ");
for (int i = 0; i < parameterTypes.length; i++) {
if (i > 0) {
// add a comma and a space between printed values
sb.append(" + \", \" ");
}
CtClass parameterType = parameterTypes[i];
boolean isArray = parameterType.isArray();
CtClass arrayType = parameterType.getComponentType();
if (isArray) {
while (arrayType.isArray()) {
arrayType = arrayType.getComponentType();
}
}
sb.append(" + \"");
try {
sb.append(parameterNameFor(method, locals, i));
} catch (Exception e) {
sb.append(i + 1);
}
sb.append("\" + \"=");
if (parameterType.isPrimitive()) {
// let the compiler handle primitive -> string
sb.append("\"+ $").append(i + 1);
} else {
String s = "org.slf4j.instrumentation.ToStringHelper.render";
sb.append("\"+ ").append(s).append("($").append(i + 1).append(')');
}
}
sb.append("+\")");
String signature = sb.toString();
return signature;
}