/**
* Adds a prefix to the original method. To make it callable only from within the framework
* itself.
*
* @param mg the MethodGen
* @param method the current method
* @param methodSequence the methods sequence number
* @param uuid the definition UUID
* @return the modified method
*/
private Method addPrefixToMethod(
final MethodGen mg, final Method method, final int methodSequence, final String uuid) {
// change the method access flags (should always be set to protected)
int accessFlags = mg.getAccessFlags();
if ((accessFlags & Constants.ACC_PROTECTED) == 0) {
// set the protected flag
accessFlags |= Constants.ACC_PROTECTED;
}
if ((accessFlags & Constants.ACC_PRIVATE) != 0) {
// clear the private flag
accessFlags &= ~Constants.ACC_PRIVATE;
}
if ((accessFlags & Constants.ACC_PUBLIC) != 0) {
// clear the public flag
accessFlags &= ~Constants.ACC_PUBLIC;
}
mg.setName(getPrefixedMethodName(method, methodSequence, mg.getClassName()));
mg.setAccessFlags(accessFlags);
mg.setMaxStack();
mg.setMaxLocals();
return mg.getMethod();
}
private static void addTimer(ClassGen cgen, Method method) {
// set up the construction tools
InstructionFactory ifact = new InstructionFactory(cgen);
InstructionList ilist = new InstructionList();
ConstantPoolGen pgen = cgen.getConstantPool();
String cname = cgen.getClassName();
MethodGen wrapgen = new MethodGen(method, cname, pgen);
wrapgen.setInstructionList(ilist);
// rename a copy of the original method
MethodGen methgen = new MethodGen(method, cname, pgen);
cgen.removeMethod(method);
String iname = methgen.getName() + "_timing";
methgen.setName(iname);
cgen.addMethod(methgen.getMethod());
Type result = methgen.getReturnType();
// compute the size of the calling parameters
Type[] parameters = methgen.getArgumentTypes();
int stackIndex = methgen.isStatic() ? 0 : 1;
for (int i = 0; i < parameters.length; i++) {
stackIndex += parameters[i].getSize();
}
// save time prior to invocation
ilist.append(
ifact.createInvoke(
"java.lang.System",
"currentTimeMillis",
Type.LONG,
Type.NO_ARGS,
Constants.INVOKESTATIC));
ilist.append(InstructionFactory.createStore(Type.LONG, stackIndex));
// call the wrapped method
int offset = 0;
short invoke = Constants.INVOKESTATIC;
if (!methgen.isStatic()) {
ilist.append(InstructionFactory.createLoad(Type.OBJECT, 0));
offset = 1;
invoke = Constants.INVOKEVIRTUAL;
}
for (int i = 0; i < parameters.length; i++) {
Type type = parameters[i];
ilist.append(InstructionFactory.createLoad(type, offset));
offset += type.getSize();
}
ilist.append(ifact.createInvoke(cname, iname, result, parameters, invoke));
// store result for return later
if (result != Type.VOID) {
ilist.append(InstructionFactory.createStore(result, stackIndex + 2));
}
// print time required for method call
ilist.append(
ifact.createFieldAccess(
"java.lang.System", "out", new ObjectType("java.io.PrintStream"), Constants.GETSTATIC));
ilist.append(InstructionConstants.DUP);
ilist.append(InstructionConstants.DUP);
String text = "Call to method " + methgen.getName() + " took ";
ilist.append(new PUSH(pgen, text));
ilist.append(
ifact.createInvoke(
"java.io.PrintStream",
"print",
Type.VOID,
new Type[] {Type.STRING},
Constants.INVOKEVIRTUAL));
ilist.append(
ifact.createInvoke(
"java.lang.System",
"currentTimeMillis",
Type.LONG,
Type.NO_ARGS,
Constants.INVOKESTATIC));
ilist.append(InstructionFactory.createLoad(Type.LONG, stackIndex));
ilist.append(InstructionConstants.LSUB);
ilist.append(
ifact.createInvoke(
"java.io.PrintStream",
"print",
Type.VOID,
new Type[] {Type.LONG},
Constants.INVOKEVIRTUAL));
ilist.append(new PUSH(pgen, " ms."));
ilist.append(
ifact.createInvoke(
"java.io.PrintStream",
"println",
Type.VOID,
new Type[] {Type.STRING},
Constants.INVOKEVIRTUAL));
// return result from wrapped method call
if (result != Type.VOID) {
ilist.append(InstructionFactory.createLoad(result, stackIndex + 2));
}
ilist.append(InstructionFactory.createReturn(result));
// finalize the constructed method
wrapgen.stripAttributes(true);
wrapgen.setMaxStack();
wrapgen.setMaxLocals();
cgen.addMethod(wrapgen.getMethod());
ilist.dispose();
}
