org.aspectj.weaver.patterns.ThisOrTargetPointcut.java Source code

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Here is the source code for org.aspectj.weaver.patterns.ThisOrTargetPointcut.java

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/* *******************************************************************
 * Copyright (c) 2002 Palo Alto Research Center, Incorporated (PARC).
 * 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://www.eclipse.org/legal/epl-v10.html 
 *  
 * Contributors: 
 *     PARC     initial implementation 
 * ******************************************************************/

package org.aspectj.weaver.patterns;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;

import org.aspectj.bridge.IMessage;
import org.aspectj.bridge.MessageUtil;
import org.aspectj.util.FuzzyBoolean;
import org.aspectj.weaver.CompressingDataOutputStream;
import org.aspectj.weaver.ISourceContext;
import org.aspectj.weaver.IntMap;
import org.aspectj.weaver.ResolvedType;
import org.aspectj.weaver.Shadow;
import org.aspectj.weaver.UnresolvedType;
import org.aspectj.weaver.VersionedDataInputStream;
import org.aspectj.weaver.WeaverMessages;
import org.aspectj.weaver.World;
import org.aspectj.weaver.ast.Literal;
import org.aspectj.weaver.ast.Test;
import org.aspectj.weaver.ast.Var;

/**
 * Corresponds to target or this pcd.
 * 
 * <p>
 * type is initially a WildTypePattern. If it stays that way, it's a this(Foo) type deal. however, the resolveBindings method may
 * convert it to a BindingTypePattern, in which case, it's a this(foo) type deal.
 * 
 * @author Erik Hilsdale
 * @author Jim Hugunin
 */
public class ThisOrTargetPointcut extends NameBindingPointcut {
    private boolean isThis;
    private TypePattern typePattern;
    private String declarationText;

    private static final int thisKindSet;
    private static final int targetKindSet;

    static {
        int thisFlags = Shadow.ALL_SHADOW_KINDS_BITS;
        int targFlags = Shadow.ALL_SHADOW_KINDS_BITS;
        for (int i = 0; i < Shadow.SHADOW_KINDS.length; i++) {
            Shadow.Kind kind = Shadow.SHADOW_KINDS[i];
            if (kind.neverHasThis()) {
                thisFlags -= kind.bit;
            }
            if (kind.neverHasTarget()) {
                targFlags -= kind.bit;
            }
        }
        thisKindSet = thisFlags;
        targetKindSet = targFlags;
    }

    public boolean isBinding() {
        return (typePattern instanceof BindingTypePattern);
    }

    public ThisOrTargetPointcut(boolean isThis, TypePattern type) {
        this.isThis = isThis;
        this.typePattern = type;
        this.pointcutKind = THIS_OR_TARGET;
        this.declarationText = (isThis ? "this(" : "target(") + type + ")";
    }

    public TypePattern getType() {
        return typePattern;
    }

    public boolean isThis() {
        return isThis;
    }

    @Override
    public Pointcut parameterizeWith(Map<String, UnresolvedType> typeVariableMap, World w) {
        ThisOrTargetPointcut ret = new ThisOrTargetPointcut(isThis,
                typePattern.parameterizeWith(typeVariableMap, w));
        ret.copyLocationFrom(this);
        return ret;
    }

    @Override
    public int couldMatchKinds() {
        return isThis ? thisKindSet : targetKindSet;
    }

    @Override
    public FuzzyBoolean fastMatch(FastMatchInfo type) {
        return FuzzyBoolean.MAYBE;
    }

    private boolean couldMatch(Shadow shadow) {
        return isThis ? shadow.hasThis() : shadow.hasTarget();
    }

    @Override
    protected FuzzyBoolean matchInternal(Shadow shadow) {
        if (!couldMatch(shadow)) {
            return FuzzyBoolean.NO;
        }
        UnresolvedType typeToMatch = isThis ? shadow.getThisType() : shadow.getTargetType();
        // optimization for case of this(Object) or target(Object)
        // works for an ExactTypePattern (and we know there are no annotations to match here of course)
        if (typePattern.getExactType().equals(ResolvedType.OBJECT)) {
            return FuzzyBoolean.YES;
        }
        return typePattern.matches(typeToMatch.resolve(shadow.getIWorld()), TypePattern.DYNAMIC);
    }

    @Override
    public void write(CompressingDataOutputStream s) throws IOException {
        s.writeByte(Pointcut.THIS_OR_TARGET);
        s.writeBoolean(isThis);
        typePattern.write(s);
        writeLocation(s);
    }

    public static Pointcut read(VersionedDataInputStream s, ISourceContext context) throws IOException {
        boolean isThis = s.readBoolean();
        TypePattern type = TypePattern.read(s, context);
        ThisOrTargetPointcut ret = new ThisOrTargetPointcut(isThis, type);
        ret.readLocation(context, s);
        return ret;
    }

    @Override
    public void resolveBindings(IScope scope, Bindings bindings) {
        typePattern = typePattern.resolveBindings(scope, bindings, true, true);

        // look for parameterized type patterns which are not supported...
        HasThisTypePatternTriedToSneakInSomeGenericOrParameterizedTypePatternMatchingStuffAnywhereVisitor visitor = new HasThisTypePatternTriedToSneakInSomeGenericOrParameterizedTypePatternMatchingStuffAnywhereVisitor();
        typePattern.traverse(visitor, null);
        if (visitor.wellHasItThen/* ? */()) {
            scope.message(
                    MessageUtil.error(WeaverMessages.format(WeaverMessages.THIS_AND_TARGET_DONT_SUPPORT_PARAMETERS),
                            getSourceLocation()));
        }
        // ??? handle non-formal
    }

    @Override
    public void postRead(ResolvedType enclosingType) {
        typePattern.postRead(enclosingType);
    }

    @Override
    public List<BindingPattern> getBindingAnnotationTypePatterns() {
        return Collections.emptyList();
    }

    @Override
    public List<BindingTypePattern> getBindingTypePatterns() {
        if (typePattern instanceof BindingTypePattern) {
            List<BindingTypePattern> l = new ArrayList<BindingTypePattern>();
            l.add((BindingTypePattern) typePattern);
            return l;
        } else {
            return Collections.emptyList();
        }
    }

    @Override
    public boolean equals(Object other) {
        if (!(other instanceof ThisOrTargetPointcut)) {
            return false;
        }
        ThisOrTargetPointcut o = (ThisOrTargetPointcut) other;
        return o.isThis == this.isThis && o.typePattern.equals(this.typePattern);
    }

    @Override
    public int hashCode() {
        int result = 17;
        result = 37 * result + (isThis ? 0 : 1);
        result = 37 * result + typePattern.hashCode();
        return result;
    }

    @Override
    public String toString() {
        return declarationText;
    }

    /**
     * Residue is the remainder of the pointcut match that couldn't be performed with the purely static information at compile time
     * and this method returns the residue of a pointcut at a particular shadow.
     */
    @Override
    protected Test findResidueInternal(Shadow shadow, ExposedState state) {
        if (!couldMatch(shadow)) {
            return Literal.FALSE;
        }

        // if no preference is specified, just say TRUE which means no residue
        if (typePattern == TypePattern.ANY) {
            return Literal.TRUE;
        }

        Var var = isThis ? shadow.getThisVar() : shadow.getTargetVar();

        return exposeStateForVar(var, typePattern, state, shadow.getIWorld());
    }

    @Override
    public Pointcut concretize1(ResolvedType inAspect, ResolvedType declaringType, IntMap bindings) {
        if (isDeclare(bindings.getEnclosingAdvice())) {
            // Enforce rule about which designators are supported in declare
            inAspect.getWorld().showMessage(IMessage.ERROR,
                    WeaverMessages.format(WeaverMessages.THIS_OR_TARGET_IN_DECLARE, isThis ? "this" : "target"),
                    bindings.getEnclosingAdvice().getSourceLocation(), null);
            return Pointcut.makeMatchesNothing(Pointcut.CONCRETE);
        }

        TypePattern newType = typePattern.remapAdviceFormals(bindings);
        if (inAspect.crosscuttingMembers != null) {
            inAspect.crosscuttingMembers.exposeType(newType.getExactType());
        }

        Pointcut ret = new ThisOrTargetPointcut(isThis, newType);
        ret.copyLocationFrom(this);
        return ret;
    }

    @Override
    public Object accept(PatternNodeVisitor visitor, Object data) {
        return visitor.visit(this, data);
    }
}