// Copyright (c) 2003-2014, Jodd Team (jodd.org). All Rights Reserved.
package jodd.proxetta.asm;
import jodd.asm.AsmUtil;
import jodd.proxetta.ProxettaException;
import jodd.asm5.ClassVisitor;
import jodd.asm5.MethodVisitor;
import jodd.asm5.AnnotationVisitor;
import jodd.asm5.ClassReader;
import jodd.asm5.Attribute;
import jodd.asm5.FieldVisitor;
import static jodd.asm5.Opcodes.ACC_ABSTRACT;
import static jodd.asm5.Opcodes.INVOKESTATIC;
import static jodd.asm5.Opcodes.RETURN;
import static jodd.asm5.Opcodes.ALOAD;
import static jodd.asm5.Opcodes.INVOKESPECIAL;
import static jodd.JoddProxetta.initMethodName;
import static jodd.proxetta.asm.ProxettaAsmUtil.INIT;
import static jodd.proxetta.asm.ProxettaAsmUtil.CLINIT;
import static jodd.proxetta.asm.ProxettaAsmUtil.DESC_VOID;
import jodd.proxetta.ProxyAspect;
import jodd.asm.AnnotationVisitorAdapter;
import jodd.asm.EmptyClassVisitor;
import java.util.List;
import java.util.ArrayList;
/**
* Proxetta class builder.
*/
public class ProxettaClassBuilder extends EmptyClassVisitor {
protected final ProxyAspect[] aspects;
protected final String suffix;
protected final String reqProxyClassName;
protected final TargetClassInfoReader targetClassInfo;
protected final WorkData wd;
/**
* Constructs new Proxetta class builder.
* @param dest destination visitor
* @param aspects set of aspects to apply
* @param suffix proxy class name suffix, may be <code>null</code>
* @param reqProxyClassName requested proxy class name, may be <code>null</code>s
* @param targetClassInfoReader target info reader, already invoked.
*/
public ProxettaClassBuilder(ClassVisitor dest, ProxyAspect[] aspects, String suffix, String reqProxyClassName, TargetClassInfoReader targetClassInfoReader) {
this.wd = new WorkData(dest);
this.aspects = aspects;
this.suffix = suffix;
this.reqProxyClassName = reqProxyClassName;
this.targetClassInfo = targetClassInfoReader;
}
/**
* Returns working data.
*/
public WorkData getWorkData() {
return wd;
}
// ---------------------------------------------------------------- header
/**
* Creates destination subclass header from current target class. Destination name is created from targets by
* adding a suffix and, optionally, a number. Destination extends the target.
*/
@Override
public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
wd.init(name, superName, this.suffix, this.reqProxyClassName);
// change access of destination
access &= ~AsmUtil.ACC_ABSTRACT;
// write destination class
wd.dest.visit(version, access, wd.thisReference, signature, wd.superName, null);
wd.proxyAspects = new ProxyAspectData[aspects.length];
for (int i = 0; i < aspects.length; i++) {
wd.proxyAspects[i] = new ProxyAspectData(wd, aspects[i], i);
}
}
// ---------------------------------------------------------------- methods and fields
/**
* Creates proxified methods and constructors.
* Destination proxy will have all constructors as a target class, using {@link jodd.proxetta.asm.ProxettaCtorBuilder}.
* Static initializers are removed, since they will be execute in target anyway.
* For each method, {@link ProxettaMethodBuilder} determines if method matches pointcut. If so, method will be proxified.
*/
@Override
public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
MethodSignatureVisitor msign = targetClassInfo.lookupMethodSignatureVisitor(access, name, desc, wd.superReference);
if (msign == null) {
return null;
}
// destination constructors [A1]
if (name.equals(INIT) == true) {
MethodVisitor mv = wd.dest.visitMethod(access, name, desc, msign.getRawSignature(), null);
return new ProxettaCtorBuilder(mv, msign, wd);
}
// ignore destination static block
if (name.equals(CLINIT) == true) {
return null;
}
return applyProxy(msign);
}
/**
* Ignores fields. Fields are not copied to the destination.
*/
@Override
public FieldVisitor visitField(int access, String name, String desc, String signature, Object value) {
return null;
}
// ---------------------------------------------------------------- annotation
/**
* Copies all destination type annotations to the target.
*/
@Override
public AnnotationVisitor visitAnnotation(String desc, boolean visible) {
AnnotationVisitor destAnn = wd.dest.visitAnnotation(desc, visible); // [A3]
return new AnnotationVisitorAdapter(destAnn);
}
// ---------------------------------------------------------------- end
/**
* Finalizes creation of destination proxy class.
*/
@Override
public void visitEnd() {
makeStaticInitBlock();
makeProxyConstructor();
processSuperMethods();
wd.dest.visitEnd();
}
/**
* Creates static initialization block that simply calls all
* advice static init methods in correct order.
*/
protected void makeStaticInitBlock() {
if (wd.adviceClinits != null) {
MethodVisitor mv = wd.dest.visitMethod(AsmUtil.ACC_STATIC, CLINIT, DESC_VOID, null, null);
mv.visitCode();
for (String name : wd.adviceClinits) {
mv.visitMethodInsn(INVOKESTATIC, wd.thisReference, name, DESC_VOID);
}
mv.visitInsn(RETURN);
mv.visitMaxs(0, 0);
mv.visitEnd();
}
}
/**
* Creates init method that simply calls all advice constructor methods in correct order.
* This created init method is called from each destination's constructor.
*/
protected void makeProxyConstructor() {
MethodVisitor mv = wd.dest.visitMethod(AsmUtil.ACC_PRIVATE | AsmUtil.ACC_FINAL, initMethodName, DESC_VOID, null, null);
mv.visitCode();
if (wd.adviceInits != null) {
for (String name : wd.adviceInits) {
mv.visitVarInsn(ALOAD, 0);
mv.visitMethodInsn(INVOKESPECIAL, wd.thisReference, name, DESC_VOID);
}
}
mv.visitInsn(RETURN);
mv.visitMaxs(0, 0);
mv.visitEnd();
}
/**
* Checks for all public super methods that are not overridden.
*/
protected void processSuperMethods() {
for (ClassReader cr : targetClassInfo.superClassReaders) {
cr.accept(new EmptyClassVisitor() {
String declaredClassName;
@Override
public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
declaredClassName = name;
}
@Override
public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
if (name.equals(INIT) || name.equals(CLINIT)) {
return null;
}
MethodSignatureVisitor msign = targetClassInfo.lookupMethodSignatureVisitor(access, name, desc, declaredClassName);
if (msign == null) {
return null;
}
return applyProxy(msign);
}
}, 0);
}
}
// ---------------------------------------------------------------- not used
/**
* Visits the source of the class (not used).
*/
@Override
public void visitSource(String source, String debug) {
// not used
}
/**
* Visits the enclosing class of the class (not used).
*/
@Override
public void visitOuterClass(String owner, String name, String desc) {
// not used
}
/**
* Visits a non standard attribute of the class (not used).
*/
@Override
public void visitAttribute(Attribute attr) {
// not used
}
/**
* Visits information about an inner class (not used).
*/
@Override
public void visitInnerClass(String name, String outerName, String innerName, int access) {
// not used
}
// ---------------------------------------------------------------- create proxy method builder if needed
/**
* Check if proxy should be applied on method and return proxy method builder if so.
* Otherwise, returns <code>null</code>.
*/
protected ProxettaMethodBuilder applyProxy(MethodSignatureVisitor msign) {
List<ProxyAspectData> aspectList = matchMethodPointcuts(msign);
if (aspectList == null) {
// no pointcuts on this method, return
return null;
}
int access = msign.getAccessFlags();
if ((access & ACC_ABSTRACT) != 0) {
throw new ProxettaException("Unable to process abstract method: " + msign);
}
wd.proxyApplied = true;
return new ProxettaMethodBuilder(msign, wd, aspectList);
}
/**
* Matches pointcuts on method. If no pointcut found, returns <code>null</code>.
*/
protected List<ProxyAspectData> matchMethodPointcuts(MethodSignatureVisitor msign) {
List<ProxyAspectData> aspectList = null;
for (ProxyAspectData aspectData : wd.proxyAspects) {
if (aspectData.apply(msign) == true) {
if (aspectList == null) {
aspectList = new ArrayList<ProxyAspectData>(wd.proxyAspects.length);
}
aspectList.add(aspectData);
}
}
return aspectList;
}
}