// Copyright (c) 2003-2014, Jodd Team (jodd.org). All Rights Reserved.
package jodd.proxetta.asm;
import jodd.asm.AsmUtil;
import jodd.asm.MethodAdapter;
import jodd.asm5.FieldVisitor;
import jodd.asm5.Label;
import jodd.asm5.MethodVisitor;
import jodd.asm5.ClassReader;
import static jodd.asm5.Opcodes.INVOKESTATIC;
import static jodd.asm5.Opcodes.ALOAD;
import static jodd.asm5.Opcodes.INVOKESPECIAL;
import static jodd.asm5.Opcodes.INVOKEVIRTUAL;
import static jodd.asm5.Opcodes.INVOKEINTERFACE;
import static jodd.proxetta.asm.ProxettaAsmUtil.*;
import static jodd.proxetta.JoddProxetta.*;
import jodd.proxetta.ProxyAspect;
import jodd.proxetta.MethodInfo;
import jodd.proxetta.ProxyAdvice;
import jodd.proxetta.ProxettaException;
import jodd.proxetta.ProxyPointcut;
import jodd.util.ClassLoaderUtil;
import jodd.io.StreamUtil;
import jodd.asm.EmptyClassVisitor;
import jodd.asm.EmptyMethodVisitor;
import java.io.InputStream;
import java.io.IOException;
import java.util.Map;
import java.util.HashMap;
/**
* Data of single aspect.
*/
@SuppressWarnings({"AnonymousClassVariableHidesContainingMethodVariable"})
final class ProxyAspectData {
final ClassReader adviceClassReader;
final ProxyAspect aspect;
final Class<? extends ProxyAdvice> advice;
final ProxyPointcut pointcut;
final int aspectIndex;
final WorkData wd; // destination class writer
String adviceReference; // advice reference
boolean ready; // is advice ready for manipulation?
int maxLocalVarOffset; // first next local var offset
ProxyAspectData(WorkData wd, ProxyAspect aspect, int aspectIndex) {
this.aspect = aspect;
this.advice = aspect.getAdvice();
this.pointcut = aspect.getPointcut();
this.aspectIndex = aspectIndex;
this.wd = wd;
adviceClassReader = getCachedAdviceClassReader(advice);
readAdviceData();
}
/**
* Delegates to aspects pointcut.
*/
boolean apply(MethodInfo msign) {
return pointcut.apply(msign);
}
// ---------------------------------------------------------------- advice reader cache
private static Map<Class<? extends ProxyAdvice>, ClassReader> adviceClassReaderCache;
/**
* Creates advice's class reader.
*/
private ClassReader createAdviceClassReader(Class<? extends ProxyAdvice> advice) {
InputStream inputStream = null;
try {
inputStream = ClassLoaderUtil.getClassAsStream(advice);
return new ClassReader(inputStream);
} catch (IOException ioex) {
throw new ProxettaException(ioex);
} finally {
StreamUtil.close(inputStream);
}
}
/**
* Returns class reader for advice.
*/
private ClassReader getCachedAdviceClassReader(Class<? extends ProxyAdvice> advice) {
if (adviceClassReaderCache == null) {
adviceClassReaderCache = new HashMap<Class<? extends ProxyAdvice>, ClassReader>();
}
ClassReader adviceReader = adviceClassReaderCache.get(advice);
if (adviceReader == null) {
adviceReader = createAdviceClassReader(advice);
adviceClassReaderCache.put(advice, adviceReader);
}
return adviceReader;
}
/**
* Returns class reader for advice.
*/
ClassReader getAdviceClassReader() {
return adviceClassReader;
}
// ---------------------------------------------------------------- read
/**
* Parse advice class to gather some advice data. Should be called before any advice use.
* Must be called only *once* per advice.
*/
private void readAdviceData() {
if (ready == true) {
return;
}
adviceClassReader.accept(new EmptyClassVisitor() {
/**
* Stores advice reference.
*/
@Override
public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
adviceReference = name;
super.visit(version, access, name, signature, superName, interfaces);
}
/**
* Prevents advice to have inner classes.
*/
@Override
public void visitInnerClass(String name, String outerName, String innerName, int access) {
if (outerName.equals(adviceReference)) {
throw new ProxettaException("Proxetta doesn't allow inner classes in/for advice: " + advice.getName());
}
super.visitInnerClass(name, outerName, innerName, access);
}
/**
* Clones advices fields to destination.
*/
@Override
public FieldVisitor visitField(int access, String name, String desc, String signature, Object value) {
wd.dest.visitField(access, adviceFieldName(name, aspectIndex), desc, signature, value); // [A5]
return super.visitField(access, name, desc, signature, value);
}
/**
* Copies advices methods to destination.
*/
@Override
public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
if (name.equals(CLINIT) == true) { // [A6]
if (desc.equals(DESC_VOID) == false) {
throw new ProxettaException("Invalid static initialization block description for advice: " + advice.getName());
}
name = clinitMethodName + methodDivider + aspectIndex;
access |= AsmUtil.ACC_PRIVATE | AsmUtil.ACC_FINAL;
wd.addAdviceClinitMethod(name);
return new MethodAdapter(wd.dest.visitMethod(access, name, desc, signature, exceptions)) {
@Override
public void visitLocalVariable(String name, String desc, String signature, Label start, Label end, int index) {
}
@Override
public void visitLineNumber(int line, Label start) {
}
@Override
public void visitMethodInsn(int opcode, String owner, String name, String desc) {
if (opcode == INVOKESTATIC) {
if (owner.equals(adviceReference)) {
owner = wd.thisReference;
name = adviceMethodName(name, aspectIndex);
}
}
super.visitMethodInsn(opcode, owner, name, desc);
}
@Override
public void visitFieldInsn(int opcode, String owner, String name, String desc) { // [F6]
if (owner.equals(adviceReference)) {
owner = wd.thisReference; // [F5]
name = adviceFieldName(name, aspectIndex);
}
super.visitFieldInsn(opcode, owner, name, desc);
}
};
} else
if (name.equals(INIT) == true) { // [A7]
if (desc.equals(DESC_VOID) == false) {
throw new ProxettaException("Advices can have only default constructors. Invalid advice: " + advice.getName());
}
name = initMethodName + methodDivider + aspectIndex;
access = ProxettaAsmUtil.makePrivateFinalAccess(access);
wd.addAdviceInitMethod(name);
return new MethodAdapter(wd.dest.visitMethod(access, name, desc, signature, exceptions)) {
@Override
public void visitLocalVariable(String name, String desc, String signature, Label start, Label end, int index) {
}
@Override
public void visitLineNumber(int line, Label start) {
}
int state; // used to detect and to ignore the first super call()
@Override
public void visitVarInsn(int opcode, int var) { // [F7]
if ((state == 0) && (opcode == ALOAD) && (var == 0)) {
state++;
return;
}
super.visitVarInsn(opcode, var);
}
@Override
public void visitMethodInsn(int opcode, String owner, String name, String desc) {
if ((state == 1) && (opcode == INVOKESPECIAL)) {
state++;
return;
}
if ((opcode == INVOKEVIRTUAL) || (opcode == INVOKEINTERFACE)) {
if (owner.equals(adviceReference)) {
owner = wd.thisReference;
name = adviceMethodName(name, aspectIndex);
}
} else
if (opcode == INVOKESTATIC) {
if (owner.equals(adviceReference)) {
owner = wd.thisReference;
name = adviceMethodName(name, aspectIndex);
}
}
super.visitMethodInsn(opcode, owner, name, desc);
}
@Override
public void visitFieldInsn(int opcode, String owner, String name, String desc) { // [F7]
if (owner.equals(adviceReference)) {
owner = wd.thisReference; // [F5]
name = adviceFieldName(name, aspectIndex);
}
super.visitFieldInsn(opcode, owner, name, desc);
}
};
} else
// other methods
if (name.equals(executeMethodName) == false) {
name = adviceMethodName(name, aspectIndex);
return new MethodAdapter(wd.dest.visitMethod(access, name, desc, signature, exceptions)) {
@Override
public void visitLocalVariable(String name, String desc, String signature, Label start, Label end, int index) {
}
@Override
public void visitLineNumber(int line, Label start) {
}
@Override
public void visitMethodInsn(int opcode, String owner, String name, String desc) {
if ((opcode == INVOKEVIRTUAL) || (opcode == INVOKEINTERFACE)) {
if (owner.equals(adviceReference)) {
owner = wd.thisReference;
name = adviceMethodName(name, aspectIndex);
}
} else
if (opcode == INVOKESTATIC || opcode == INVOKESPECIAL) {
if (owner.equals(adviceReference)) {
owner = wd.thisReference;
name = adviceMethodName(name, aspectIndex);
}
}
super.visitMethodInsn(opcode, owner, name, desc);
}
@Override
public void visitFieldInsn(int opcode, String owner, String name, String desc) { // replace field references
if (owner.equals(adviceReference)) {
owner = wd.thisReference;
name = adviceFieldName(name, aspectIndex);
}
super.visitFieldInsn(opcode, owner, name, desc);
}
};
}
// Parse EXECUTE method, just to gather some info, real parsing will come later
//return new MethodAdapter(new EmptyMethodVisitor()) { // toask may we replace this with the following code?
return new EmptyMethodVisitor() {
@Override
public void visitVarInsn(int opcode, int var) {
if (isStoreOpcode(opcode)) {
if (var > maxLocalVarOffset) {
maxLocalVarOffset = var; // find max local var offset
}
}
super.visitVarInsn(opcode, var);
}
};
// return super.visitMethod(access, name, desc, signature, exceptions);
}
}, 0);
maxLocalVarOffset += 2; // increment offset by 2 because var on last index may be a dword value
ready = true;
}
}