org.aspectj.weaver.JoinPointSignatureIterator Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of aspectjtools Show documentation
Show all versions of aspectjtools Show documentation
AspectJ tools most notably contains the AspectJ compiler (AJC). AJC applies aspects to Java classes during
compilation, fully replacing Javac for plain Java classes and also compiling native AspectJ or annotation-based
@AspectJ syntax. Furthermore, AJC can weave aspects into existing class files in a post-compile binary weaving step.
This library is a superset of AspectJ weaver and hence also of AspectJ runtime.
/* *******************************************************************
* Copyright (c) 2005 Contributors.
* All rights reserved.
* This program and the accompanying materials are made available
* under the terms of the Eclipse Public License v 2.0
* which accompanies this distribution and is available at
* https://www.eclipse.org/org/documents/epl-2.0/EPL-2.0.txt
*
* Contributors:
* Adrian Colyer Initial implementation
* ******************************************************************/
package org.aspectj.weaver;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.Set;
/**
* Iterates over the signatures of a join point, calculating new signatures lazily to minimize processing and to avoid unneccessary
* "can't find type" errors. Iterator can be cached and reused by calling the "reset" method between iterations.
*/
public class JoinPointSignatureIterator implements Iterator {
ResolvedType firstDefiningType;
private Member signaturesOfMember;
private ResolvedMember firstDefiningMember;
private World world;
private List discoveredSignatures = new ArrayList<>();
private List additionalSignatures = Collections.emptyList();
private Iterator discoveredSignaturesIterator = null;
private Iterator superTypeIterator = null;
private boolean isProxy = false;
private Set visitedSuperTypes = new HashSet<>();
private List yetToBeProcessedSuperMembers = null;
private boolean iteratingOverDiscoveredSignatures = true;
private boolean couldBeFurtherAsYetUndiscoveredSignatures = true;
private final static UnresolvedType jlrProxy = UnresolvedType.forSignature("Ljava/lang/reflect/Proxy;");
public JoinPointSignatureIterator(Member joinPointSignature, World world) {
this.signaturesOfMember = joinPointSignature;
this.world = world;
addSignaturesUpToFirstDefiningMember();
if (!shouldWalkUpHierarchy()) {
couldBeFurtherAsYetUndiscoveredSignatures = false;
}
}
public void reset() {
discoveredSignaturesIterator = discoveredSignatures.iterator();
additionalSignatures.clear();
iteratingOverDiscoveredSignatures = true;
}
public boolean hasNext() {
if (iteratingOverDiscoveredSignatures && discoveredSignaturesIterator.hasNext()) {
return true;
} else if (couldBeFurtherAsYetUndiscoveredSignatures) {
if (additionalSignatures.size() > 0) {
return true;
} else {
return findSignaturesFromSupertypes();
}
} else {
return false;
}
}
public JoinPointSignature next() {
if (iteratingOverDiscoveredSignatures && discoveredSignaturesIterator.hasNext()) {
return discoveredSignaturesIterator.next();
} else {
if (additionalSignatures.size() > 0) {
return additionalSignatures.remove(0);
}
}
throw new NoSuchElementException();
}
public void remove() {
throw new UnsupportedOperationException("can't remove from JoinPointSignatureIterator");
}
/**
* Walk up the hierarchy creating one member for each type up to and including the first defining type.
*/
private void addSignaturesUpToFirstDefiningMember() {
ResolvedType originalDeclaringType = signaturesOfMember.getDeclaringType().resolve(world);
ResolvedType superType = originalDeclaringType.getSuperclass();
if (superType != null && superType.equals(jlrProxy)) {
// Proxy types are generated without any regard to generics (pr268419) and so the member walking
// should also ignore them
isProxy = true;
}
// is it the array constructor join point?
if (world.isJoinpointArrayConstructionEnabled() && originalDeclaringType.isArray()) {
Member m = signaturesOfMember;
ResolvedMember rm = new ResolvedMemberImpl(m.getKind(), m.getDeclaringType(), m.getModifiers(), m.getReturnType(), m
.getName(), m.getParameterTypes());
discoveredSignatures.add(new JoinPointSignature(rm, originalDeclaringType));
couldBeFurtherAsYetUndiscoveredSignatures = false;
return;
}
firstDefiningMember = (signaturesOfMember instanceof ResolvedMember ?
(ResolvedMember) signaturesOfMember: signaturesOfMember.resolve(world));
if (firstDefiningMember == null) {
couldBeFurtherAsYetUndiscoveredSignatures = false;
return;
}
// declaringType can be unresolved if we matched a synthetic member generated by Aj...
// should be fixed elsewhere but add this resolve call on the end for now so that we can
// focus on one problem at a time...
firstDefiningType = firstDefiningMember.getDeclaringType().resolve(world);
if (firstDefiningType != originalDeclaringType) {
if (signaturesOfMember.getKind() == Member.CONSTRUCTOR) {
return;
}
}
if (originalDeclaringType == firstDefiningType) {
// a common case
discoveredSignatures.add(new JoinPointSignature(firstDefiningMember, originalDeclaringType));
} else {
List declaringTypes = new ArrayList<>();
accumulateTypesInBetween(originalDeclaringType, firstDefiningType, declaringTypes);
for (ResolvedType declaringType : declaringTypes) {
discoveredSignatures.add(new JoinPointSignature(firstDefiningMember, declaringType));
}
}
}
/**
* Build a list containing every type between subtype and supertype, inclusively.
*/
private void accumulateTypesInBetween(ResolvedType subType, ResolvedType superType, List types) {
types.add(subType);
if (subType == superType) {
return;
} else {
for (Iterator iter = subType.getDirectSupertypes(); iter.hasNext();) {
ResolvedType parent = iter.next();
if (superType.isAssignableFrom(parent, true)) {
accumulateTypesInBetween(parent, superType, types);
}
}
}
}
private boolean shouldWalkUpHierarchy() {
if (signaturesOfMember.getKind() == Member.CONSTRUCTOR) {
return false;
}
if (signaturesOfMember.getKind() == Member.FIELD) {
return false;
}
if (Modifier.isStatic(signaturesOfMember.getModifiers())) {
return false;
}
return true;
}
private boolean findSignaturesFromSupertypes() {
iteratingOverDiscoveredSignatures = false;
if (superTypeIterator == null) {
superTypeIterator = firstDefiningType.getDirectSupertypes();
}
if (superTypeIterator.hasNext()) {
ResolvedType superType = superTypeIterator.next();
if (isProxy && (superType.isGenericType() || superType.isParameterizedType())) {
superType = superType.getRawType();
}
if (visitedSuperTypes.contains(superType)) {
return findSignaturesFromSupertypes();
} else {
// we haven't looked in this type yet
visitedSuperTypes.add(superType);
if (superType.isMissing()) {
// issue a warning, stop looking for join point signatures in this line
warnOnMissingType(superType);
return findSignaturesFromSupertypes();
}
ResolvedMemberImpl foundMember = (ResolvedMemberImpl) superType.lookupResolvedMember(firstDefiningMember, true,
isProxy);
if (foundMember != null && isVisibleTo(firstDefiningMember, foundMember)) {
List declaringTypes = new ArrayList<>();
// declaring type can be unresolved if the member can from an ITD...
ResolvedType resolvedDeclaringType = foundMember.getDeclaringType().resolve(world);
accumulateTypesInBetween(superType, resolvedDeclaringType, declaringTypes);
for (ResolvedType declaringType : declaringTypes) {
JoinPointSignature member = null;
if (isProxy) {
if (declaringType.isGenericType() || declaringType.isParameterizedType()) {
declaringType = declaringType.getRawType();
}
}
member = new JoinPointSignature(foundMember, declaringType);
discoveredSignatures.add(member); // for next time we are reset
if (additionalSignatures == Collections.EMPTY_LIST) {
additionalSignatures = new ArrayList<>();
}
additionalSignatures.add(member); // for this time
}
// if this was a parameterized type, look in the generic type that backs it too
if (!isProxy && superType.isParameterizedType() && (foundMember.backingGenericMember != null)) {
JoinPointSignature member = new JoinPointSignature(foundMember.backingGenericMember,
foundMember.declaringType.resolve(world));
discoveredSignatures.add(member); // for next time we are reset
if (additionalSignatures == Collections.EMPTY_LIST) {
additionalSignatures = new ArrayList<>();
}
additionalSignatures.add(member); // for this time
}
if (yetToBeProcessedSuperMembers == null) {
yetToBeProcessedSuperMembers = new ArrayList<>();
}
yetToBeProcessedSuperMembers.add(new SearchPair(foundMember, superType));
return true;
} else {
return findSignaturesFromSupertypes();
}
}
}
if (yetToBeProcessedSuperMembers != null && !yetToBeProcessedSuperMembers.isEmpty()) {
SearchPair nextUp = yetToBeProcessedSuperMembers.remove(0);
firstDefiningType = nextUp.type;
firstDefiningMember = nextUp.member;
superTypeIterator = null;
return findSignaturesFromSupertypes();
}
couldBeFurtherAsYetUndiscoveredSignatures = false;
return false;
}
/**
* Returns true if the parent member is visible to the child member In the same declaring type this is always true, otherwise if
* parent is private it is false.
*
* @param childMember
* @param parentMember
* @return
*/
private boolean isVisibleTo(ResolvedMember childMember, ResolvedMember parentMember) {
if (childMember.getDeclaringType().equals(parentMember.getDeclaringType())) {
return true;
}
if (Modifier.isPrivate(parentMember.getModifiers())) {
return false;
} else {
return true;
}
}
private void warnOnMissingType(ResolvedType missing) {
if (missing instanceof MissingResolvedTypeWithKnownSignature) {
// which it should be...
MissingResolvedTypeWithKnownSignature mrt = (MissingResolvedTypeWithKnownSignature) missing;
mrt.raiseWarningOnJoinPointSignature(signaturesOfMember.toString());
}
}
private static class SearchPair {
public ResolvedMember member;
public ResolvedType type;
public SearchPair(ResolvedMember member, ResolvedType type) {
this.member = member;
this.type = type;
}
}
}