org.aspectj.weaver.loadtime.ConcreteAspectCodeGen Maven / Gradle / Ivy
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/*******************************************************************************
* Copyright (c) 2005 Contributors.
* All rights reserved.
* This program and the accompanying materials are made available
* under the terms of the Eclipse Public License v1.0
* which accompanies this distribution and is available at
* http://eclipse.org/legal/epl-v10.html
*
* Contributors:
* Alexandre Vasseur initial implementation
*******************************************************************************/
package org.aspectj.weaver.loadtime;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.aspectj.apache.bcel.Constants;
import org.aspectj.apache.bcel.classfile.ConstantPool;
import org.aspectj.apache.bcel.classfile.JavaClass;
import org.aspectj.apache.bcel.classfile.annotation.AnnotationGen;
import org.aspectj.apache.bcel.classfile.annotation.ClassElementValue;
import org.aspectj.apache.bcel.classfile.annotation.ElementValue;
import org.aspectj.apache.bcel.classfile.annotation.NameValuePair;
import org.aspectj.apache.bcel.classfile.annotation.SimpleElementValue;
import org.aspectj.apache.bcel.generic.FieldGen;
import org.aspectj.apache.bcel.generic.InstructionConstants;
import org.aspectj.apache.bcel.generic.InstructionFactory;
import org.aspectj.apache.bcel.generic.InstructionHandle;
import org.aspectj.apache.bcel.generic.InstructionList;
import org.aspectj.apache.bcel.generic.LocalVariableTag;
import org.aspectj.apache.bcel.generic.ObjectType;
import org.aspectj.apache.bcel.generic.Type;
import org.aspectj.bridge.IMessage;
import org.aspectj.bridge.Message;
import org.aspectj.weaver.AjAttribute;
import org.aspectj.weaver.AnnotationAJ;
import org.aspectj.weaver.GeneratedReferenceTypeDelegate;
import org.aspectj.weaver.ReferenceType;
import org.aspectj.weaver.ResolvedMember;
import org.aspectj.weaver.ResolvedType;
import org.aspectj.weaver.UnresolvedType;
import org.aspectj.weaver.World;
import org.aspectj.weaver.bcel.BcelAnnotation;
import org.aspectj.weaver.bcel.BcelPerClauseAspectAdder;
import org.aspectj.weaver.bcel.BcelWorld;
import org.aspectj.weaver.bcel.LazyClassGen;
import org.aspectj.weaver.bcel.LazyMethodGen;
import org.aspectj.weaver.loadtime.definition.Definition;
import org.aspectj.weaver.loadtime.definition.Definition.AdviceKind;
import org.aspectj.weaver.loadtime.definition.Definition.DeclareAnnotationKind;
import org.aspectj.weaver.loadtime.definition.Definition.PointcutAndAdvice;
import org.aspectj.weaver.patterns.BasicTokenSource;
import org.aspectj.weaver.patterns.DeclareAnnotation;
import org.aspectj.weaver.patterns.ISignaturePattern;
import org.aspectj.weaver.patterns.ITokenSource;
import org.aspectj.weaver.patterns.PatternParser;
import org.aspectj.weaver.patterns.PerClause;
import org.aspectj.weaver.patterns.TypePattern;
/**
* Generates bytecode for concrete-aspect.
*
* The concrete aspect is generated annotation style aspect (so traditional Java constructs annotated with our AspectJ annotations).
* As it is built during aop.xml definitions registration we perform the type munging for perclause, ie. aspectOf() artifact
* directly, instead of waiting for it to go thru the weaver (that we are in the middle of configuring).
*
* @author Alexandre Vasseur
* @author Andy Clement
*/
public class ConcreteAspectCodeGen {
private final static String[] EMPTY_STRINGS = new String[0];
private final static Type[] EMPTY_TYPES = new Type[0];
/**
* Concrete aspect definition we build for
*/
private final Definition.ConcreteAspect concreteAspect;
/**
* World for which we build for
*/
private final World world;
/**
* Set to true when all is checks are verified
*/
private boolean isValid = false;
/**
* The parent aspect, not concretized
*/
private ResolvedType parent;
/**
* Aspect perClause, used for direct munging of aspectOf artifacts
*/
private PerClause perclause;
/**
* Bytecode for the generated class
*/
private byte[] bytes;
/**
* Create a new generator for a concrete aspect
*
* @param concreteAspect the aspect definition
* @param world the related world (for type resolution, etc)
*/
ConcreteAspectCodeGen(Definition.ConcreteAspect concreteAspect, World world) {
this.concreteAspect = concreteAspect;
this.world = world;
}
/**
* Checks that concrete aspect is valid.
*
* @return true if ok, false otherwise
*/
public boolean validate() {
if (!(world instanceof BcelWorld)) {
reportError("Internal error: world must be of type BcelWorld");
return false;
}
// name must be undefined so far
// TODO only convert the name to signature once, probably earlier than this
ResolvedType current = world.lookupBySignature(UnresolvedType.forName(concreteAspect.name).getSignature());
if (current != null && !current.isMissing()) {
reportError("Attempt to concretize but chosen aspect name already defined: " + stringify());
return false;
}
if (concreteAspect.pointcutsAndAdvice.size() != 0) {
isValid = true;
return true;
}
if (concreteAspect.declareAnnotations.size()!=0) {
isValid = true;
return true;
}
// it can happen that extends is null, for precedence only declaration
if (concreteAspect.extend == null && concreteAspect.precedence != null) {
if (concreteAspect.pointcuts.isEmpty()) {
isValid = true;
// m_perClause = new PerSingleton();
parent = null;
return true;// no need to checks more in that special case
} else {
reportError("Attempt to use nested pointcuts without extends clause: " + stringify());
return false;
}
}
String parentAspectName = concreteAspect.extend;
if (parentAspectName.indexOf("<") != -1) {
// yikes, generic parent
parent = world.resolve(UnresolvedType.forName(parentAspectName), true);
if (parent.isMissing()) {
reportError("Unable to resolve type reference: " + stringify());
return false;
}
if (parent.isParameterizedType()) {
UnresolvedType[] typeParameters = parent.getTypeParameters();
for (int i = 0; i < typeParameters.length; i++) {
UnresolvedType typeParameter = typeParameters[i];
if (typeParameter instanceof ResolvedType && ((ResolvedType) typeParameter).isMissing()) {
reportError("Unablet to resolve type parameter '" + typeParameter.getName() + "' from " + stringify());
return false;
}
}
}
} else {
parent = world.resolve(concreteAspect.extend, true);
}
// handle inner classes
if (parent.isMissing()) {
// fallback on inner class lookup mechanism
String fixedName = concreteAspect.extend;
int hasDot = fixedName.lastIndexOf('.');
while (hasDot > 0) {
char[] fixedNameChars = fixedName.toCharArray();
fixedNameChars[hasDot] = '$';
fixedName = new String(fixedNameChars);
hasDot = fixedName.lastIndexOf('.');
parent = world.resolve(UnresolvedType.forName(fixedName), true);
if (!parent.isMissing()) {
break;
}
}
}
if (parent.isMissing()) {
reportError("Cannot find parent aspect for: " + stringify());
return false;
}
// extends must be abstract (allow for special case of Object where just using aspect for deows)
if (!(parent.isAbstract() || parent.equals(ResolvedType.OBJECT))) {
reportError("Attempt to concretize a non-abstract aspect: " + stringify());
return false;
}
// m_parent must be aspect (allow for special case of Object where just using aspect for deows)
if (!(parent.isAspect() || parent.equals(ResolvedType.OBJECT))) {
reportError("Attempt to concretize a non aspect: " + stringify());
return false;
}
// must have all abstractions defined
List elligibleAbstractions = new ArrayList();
Collection abstractMethods = getOutstandingAbstractMethods(parent);
for (ResolvedMember method : abstractMethods) {
if ("()V".equals(method.getSignature())) {
String n = method.getName();
// Allow for the abstract pointcut being from a code style
// aspect compiled with -1.5 (see test for 128744)
if (n.startsWith("ajc$pointcut")) {
n = n.substring(14);
n = n.substring(0, n.indexOf("$"));
elligibleAbstractions.add(n);
} else if (hasPointcutAnnotation(method)) {
elligibleAbstractions.add(method.getName());
} else {
// error, an outstanding abstract method that can't be
// concretized in XML
reportError("Abstract method '" + method.toString() + "' cannot be concretized in XML: " + stringify());
return false;
}
} else {
if (method.getName().startsWith("ajc$pointcut") || hasPointcutAnnotation(method)) {
// it may be a pointcut but it doesn't meet the requirements for XML concretization
reportError("Abstract method '"
+ method.toString()
+ "' cannot be concretized as a pointcut (illegal signature, must have no arguments, must return void): "
+ stringify());
return false;
} else {
// error, an outstanding abstract method that can't be
// concretized in XML
reportError("Abstract method '" + method.toString() + "' cannot be concretized in XML: " + stringify());
return false;
}
}
}
List pointcutNames = new ArrayList();
for (Definition.Pointcut abstractPc : concreteAspect.pointcuts) {
pointcutNames.add(abstractPc.name);
}
for (String elligiblePc : elligibleAbstractions) {
if (!pointcutNames.contains(elligiblePc)) {
reportError("Abstract pointcut '" + elligiblePc + "' not configured: " + stringify());
return false;
}
}
if (concreteAspect.perclause != null) {
String perclauseString = concreteAspect.perclause;
if (perclauseString.startsWith("persingleton")) {
} else if (perclauseString.startsWith("percflow")) {
} else if (perclauseString.startsWith("pertypewithin")) {
} else if (perclauseString.startsWith("perthis")) {
} else if (perclauseString.startsWith("pertarget")) {
} else if (perclauseString.startsWith("percflowbelow")) {
} else {
reportError("Unrecognized per clause specified " + stringify());
return false;
}
}
isValid = true;
return isValid;
}
private Collection getOutstandingAbstractMethods(ResolvedType type) {
Map collector = new HashMap();
// let's get to the top of the hierarchy and then walk down ...
// recording abstract methods then removing
// them if they get defined further down the hierarchy
getOutstandingAbstractMethodsHelper(type, collector);
return collector.values();
}
// We are trying to determine abstract methods left over at the bottom of a
// hierarchy that have not been concretized.
private void getOutstandingAbstractMethodsHelper(ResolvedType type, Map collector) {
if (type == null) {
return;
}
// Get to the top
if (!type.equals(ResolvedType.OBJECT)) {
if (type.getSuperclass() != null) {
getOutstandingAbstractMethodsHelper(type.getSuperclass(), collector);
}
}
ResolvedMember[] rms = type.getDeclaredMethods();
if (rms != null) {
for (int i = 0; i < rms.length; i++) {
ResolvedMember member = rms[i];
String key = member.getName() + member.getSignature();
if (member.isAbstract()) {
collector.put(key, member);
} else {
collector.remove(key);
}
}
}
}
/**
* Rebuild the XML snip that defines this concrete aspect, for log error purpose
*
* @return string repr.
*/
private String stringify() {
StringBuffer sb = new StringBuffer(" emptyList(), true, cg.getConstantPool());
cg.addAnnotation(ag);
} else {
// List elems = new ArrayList();
List elems = new ArrayList();
elems.add(new NameValuePair("value",
new SimpleElementValue(ElementValue.STRING, cg.getConstantPool(), perclauseString), cg.getConstantPool()));
AnnotationGen ag = new AnnotationGen(new ObjectType("org/aspectj/lang/annotation/Aspect"), elems, true,
cg.getConstantPool());
cg.addAnnotation(ag);
}
if (concreteAspect.precedence != null) {
SimpleElementValue svg = new SimpleElementValue(ElementValue.STRING, cg.getConstantPool(), concreteAspect.precedence);
List elems = new ArrayList();
elems.add(new NameValuePair("value", svg, cg.getConstantPool()));
AnnotationGen agprec = new AnnotationGen(new ObjectType("org/aspectj/lang/annotation/DeclarePrecedence"), elems, true,
cg.getConstantPool());
cg.addAnnotation(agprec);
}
// default constructor
LazyMethodGen init = new LazyMethodGen(Modifier.PUBLIC, Type.VOID, "", EMPTY_TYPES, EMPTY_STRINGS, cg);
InstructionList cbody = init.getBody();
cbody.append(InstructionConstants.ALOAD_0);
cbody.append(cg.getFactory().createInvoke(parentName, "", Type.VOID, EMPTY_TYPES, Constants.INVOKESPECIAL));
cbody.append(InstructionConstants.RETURN);
cg.addMethodGen(init);
for (Iterator it = concreteAspect.pointcuts.iterator(); it.hasNext();) {
Definition.Pointcut abstractPc = (Definition.Pointcut) it.next();
// TODO AV - respect visibility instead of opening up as public?
LazyMethodGen mg = new LazyMethodGen(Modifier.PUBLIC, Type.VOID, abstractPc.name, EMPTY_TYPES, EMPTY_STRINGS, cg);
SimpleElementValue svg = new SimpleElementValue(ElementValue.STRING, cg.getConstantPool(), abstractPc.expression);
List elems = new ArrayList();
elems.add(new NameValuePair("value", svg, cg.getConstantPool()));
AnnotationGen mag = new AnnotationGen(new ObjectType("org/aspectj/lang/annotation/Pointcut"), elems, true,
cg.getConstantPool());
AnnotationAJ max = new BcelAnnotation(mag, world);
mg.addAnnotation(max);
InstructionList body = mg.getBody();
body.append(InstructionConstants.RETURN);
cg.addMethodGen(mg);
}
// Construct any defined declare error/warnings
if (concreteAspect.deows.size() > 0) {
int counter = 1;
for (Definition.DeclareErrorOrWarning deow : concreteAspect.deows) {
// Building this:
// @DeclareWarning("call(* javax.sql..*(..)) && !within(org.xyz.daos..*)")
// static final String aMessage = "Only DAOs should be calling JDBC.";
FieldGen field = new FieldGen(Modifier.FINAL, ObjectType.STRING, "rule" + (counter++), cg.getConstantPool());
SimpleElementValue svg = new SimpleElementValue(ElementValue.STRING, cg.getConstantPool(), deow.pointcut);
List elems = new ArrayList();
elems.add(new NameValuePair("value", svg, cg.getConstantPool()));
AnnotationGen mag = new AnnotationGen(new ObjectType("org/aspectj/lang/annotation/Declare"
+ (deow.isError ? "Error" : "Warning")), elems, true, cg.getConstantPool());
field.addAnnotation(mag);
field.setValue(deow.message);
cg.addField(field, null);
}
}
if (concreteAspect.pointcutsAndAdvice.size() > 0) {
int adviceCounter = 1;
for (PointcutAndAdvice paa : concreteAspect.pointcutsAndAdvice) {
generateAdviceMethod(paa, adviceCounter, cg);
adviceCounter++;
}
}
if (concreteAspect.declareAnnotations.size()>0) {
int decCounter = 1;
for (Definition.DeclareAnnotation da: concreteAspect.declareAnnotations) {
generateDeclareAnnotation(da,decCounter++,cg);
}
}
// handle the perClause
ReferenceType rt = new ReferenceType(ResolvedType.forName(concreteAspect.name).getSignature(), world);
GeneratedReferenceTypeDelegate grtd = new GeneratedReferenceTypeDelegate(rt);
grtd.setSuperclass(parent);
rt.setDelegate(grtd);
BcelPerClauseAspectAdder perClauseMunger = new BcelPerClauseAspectAdder(rt, perclauseKind);
perClauseMunger.forceMunge(cg, false);
// TODO AV - unsafe cast
// register the fresh new class into the world repository as it does not
// exist on the classpath anywhere
JavaClass jc = cg.getJavaClass((BcelWorld) world);
((BcelWorld) world).addSourceObjectType(jc, true);
bytes = jc.getBytes();
return bytes;
}
/**
* The DeclareAnnotation object encapsulates an method/field/type descriptor and an annotation. This uses a DeclareAnnotation object
* captured from the XML (something like ' values = new ArrayList();
int pos = paren+1;
int depth = 0;
int len = annotationString.length();
int start = pos;
while (pos elems = new ArrayList();
return new AnnotationGen(new ObjectType(annoname), elems, true, cp);
}
/**
* Construct the annotation that indicates this is a declare
*/
/**
* The PointcutAndAdvice object encapsulates an advice kind, a pointcut and names a Java method in a particular class. Generate
* an annotation style advice that has that pointcut whose implementation delegates to the Java method.
*/
private void generateAdviceMethod(PointcutAndAdvice paa, int adviceCounter, LazyClassGen cg) {
// Check: Verify the class to be called does exist:
ResolvedType delegateClass = world.resolve(UnresolvedType.forName(paa.adviceClass));
if (delegateClass.isMissing()) {
reportError("Class to invoke cannot be found: '" + paa.adviceClass + "'");
return;
}
// Generate a name for this advice, includes advice kind plus a counter
String adviceName = new StringBuilder("generated$").append(paa.adviceKind.toString().toLowerCase()).append("$advice$")
.append(adviceCounter).toString();
// Build the annotation that encapsulates the pointcut
AnnotationAJ aaj = buildAdviceAnnotation(cg, paa);
// Chop up the supplied advice method string into its pieces.
// Example: foo(JoinPoint jp, java.lang.String string)
// JoinPoint and friends are recognized (so dont need fq package)
String method = paa.adviceMethod;
int paren = method.indexOf("(");
String methodName = method.substring(0, paren);
String signature = method.substring(paren);
// Check: signature looks ok
if (signature.charAt(0) != '(' || !signature.endsWith(")")) {
reportError("Badly formatted parameter signature: '" + method + "'");
return;
}
// Extract parameter types and names
List paramTypes = new ArrayList();
List paramNames = new ArrayList();
if (signature.charAt(1) != ')') {
// there are parameters to convert into a signature
StringBuilder convertedSignature = new StringBuilder("(");
boolean paramsBroken = false;
int pos = 1;
while (pos < signature.length() && signature.charAt(pos) != ')' && !paramsBroken) {
int nextChunkEndPos = signature.indexOf(',', pos);
if (nextChunkEndPos == -1) {
nextChunkEndPos = signature.indexOf(')', pos);
}
// chunk will be a type plus a space plus a name
String nextChunk = signature.substring(pos, nextChunkEndPos).trim();
int space = nextChunk.indexOf(" ");
ResolvedType resolvedParamType = null;
if (space == -1) {
// There is no parameter name, hopefully not needed!
if (nextChunk.equals("JoinPoint")) {
nextChunk = "org.aspectj.lang.JoinPoint";
} else if (nextChunk.equals("JoinPoint.StaticPart")) {
nextChunk = "org.aspectj.lang.JoinPoint$StaticPart";
} else if (nextChunk.equals("ProceedingJoinPoint")) {
nextChunk = "org.aspectj.lang.ProceedingJoinPoint";
}
UnresolvedType unresolvedParamType = UnresolvedType.forName(nextChunk);
resolvedParamType = world.resolve(unresolvedParamType);
} else {
String typename = nextChunk.substring(0, space);
if (typename.equals("JoinPoint")) {
typename = "org.aspectj.lang.JoinPoint";
} else if (typename.equals("JoinPoint.StaticPart")) {
typename = "org.aspectj.lang.JoinPoint$StaticPart";
} else if (typename.equals("ProceedingJoinPoint")) {
typename = "org.aspectj.lang.ProceedingJoinPoint";
}
UnresolvedType unresolvedParamType = UnresolvedType.forName(typename);
resolvedParamType = world.resolve(unresolvedParamType);
String paramname = nextChunk.substring(space).trim();
paramNames.add(paramname);
}
if (resolvedParamType.isMissing()) {
reportError("Cannot find type specified as parameter: '" + nextChunk + "' from signature '" + signature + "'");
paramsBroken = true;
}
paramTypes.add(Type.getType(resolvedParamType.getSignature()));
convertedSignature.append(resolvedParamType.getSignature());
pos = nextChunkEndPos + 1;
}
convertedSignature.append(")");
signature = convertedSignature.toString();
if (paramsBroken) {
return;
}
}
Type returnType = Type.VOID;
// If around advice we must find the actual delegate method and use its return type
if (paa.adviceKind == AdviceKind.Around) {
ResolvedMember[] methods = delegateClass.getDeclaredMethods();
ResolvedMember found = null;
for (ResolvedMember candidate : methods) {
if (candidate.getName().equals(methodName)) {
UnresolvedType[] cparms = candidate.getParameterTypes();
if (cparms.length == paramTypes.size()) {
boolean paramsMatch = true;
for (int i = 0; i < cparms.length; i++) {
if (!cparms[i].getSignature().equals(paramTypes.get(i).getSignature())) {
paramsMatch = false;
break;
}
}
if (paramsMatch) {
found = candidate;
break;
}
}
}
}
if (found != null) {
returnType = Type.getType(found.getReturnType().getSignature());
} else {
reportError("Unable to find method to invoke. In class: " + delegateClass.getName() + " cant find "
+ paa.adviceMethod);
return;
}
}
// Time to construct the method itself:
LazyMethodGen advice = new LazyMethodGen(Modifier.PUBLIC, returnType, adviceName, paramTypes.toArray(new Type[paramTypes
.size()]), EMPTY_STRINGS, cg);
InstructionList adviceBody = advice.getBody();
// Generate code to load the parameters
int pos = 1; // first slot after 'this'
for (int i = 0; i < paramTypes.size(); i++) {
adviceBody.append(InstructionFactory.createLoad(paramTypes.get(i), pos));
pos += paramTypes.get(i).getSize();
}
// Generate the delegate call
adviceBody.append(cg.getFactory().createInvoke(paa.adviceClass, methodName, signature + returnType.getSignature(),
Constants.INVOKESTATIC));
// Generate the right return
if (returnType == Type.VOID) {
adviceBody.append(InstructionConstants.RETURN);
} else {
if (returnType.getSignature().length() < 2) {
String sig = returnType.getSignature();
if (sig.equals("F")) {
adviceBody.append(InstructionConstants.FRETURN);
} else if (sig.equals("D")) {
adviceBody.append(InstructionConstants.DRETURN);
} else if (sig.equals("J")) {
adviceBody.append(InstructionConstants.LRETURN);
} else {
adviceBody.append(InstructionConstants.IRETURN);
}
} else {
adviceBody.append(InstructionConstants.ARETURN);
}
}
// Add the annotation
advice.addAnnotation(aaj);
InstructionHandle start = adviceBody.getStart();
// Setup the local variable targeters so that the binding will work
String sig = concreteAspect.name.replace('.', '/');
start.addTargeter(new LocalVariableTag("L" + sig + ";", "this", 0, start.getPosition()));
if (paramNames.size() > 0) {
for (int i = 0; i < paramNames.size(); i++) {
start.addTargeter(new LocalVariableTag(paramTypes.get(i).getSignature(), paramNames.get(i), i + 1, start
.getPosition()));
}
}
// Record the new method in the class
cg.addMethodGen(advice);
}
/**
* For the given PointcutAndAdvice build the correct advice annotation.
*/
private AnnotationAJ buildAdviceAnnotation(LazyClassGen cg, PointcutAndAdvice paa) {
SimpleElementValue svg = new SimpleElementValue(ElementValue.STRING, cg.getConstantPool(), paa.pointcut);
List elems = new ArrayList();
elems.add(new NameValuePair("value", svg, cg.getConstantPool()));
AnnotationGen mag = new AnnotationGen(new ObjectType("org/aspectj/lang/annotation/" + paa.adviceKind.toString()), elems,
true, cg.getConstantPool());
AnnotationAJ aaj = new BcelAnnotation(mag, world);
return aaj;
}
/**
* Error reporting
*
* @param message
*/
private void reportError(String message) {
world.getMessageHandler().handleMessage(new Message(message, IMessage.ERROR, null, null));
}
}