org.aspectj/org.aspectj.ajdt.core/src/org/aspectj/ajdt/internal/compiler/ast/IfPseudoToken.java

/* *******************************************************************
 * 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 Common Public License v1.0 
 * which accompanies this distribution and is available at 
 * http://www.eclipse.org/legal/cpl-v10.html 
 *  
 * Contributors: 
 *     Xerox/PARC     initial implementation 
 * ******************************************************************/


package org.aspectj.ajdt.internal.compiler.ast;

import java.lang.reflect.Modifier;

import org.aspectj.ajdt.internal.compiler.lookup.EclipseWorld;
import org.aspectj.weaver.*;
import org.aspectj.weaver.ResolvedMember;
import org.aspectj.weaver.patterns.*;
import org.eclipse.jdt.internal.compiler.CompilationResult;
import org.eclipse.jdt.internal.compiler.ast.*;
import org.eclipse.jdt.internal.compiler.lookup.TypeBinding;
import org.eclipse.jdt.internal.compiler.parser.*;


/**
 * (formals*): ... if(expr) ...
 * 
 * generates the following:
 * public static final boolean ajc$if_N(formals*, [thisJoinPoints as needed]) {
 *     return expr;
 * }
 * 
 * Here's the complicated bit, it deals with cflow:
 * 	(a): ... this(a) && cflow(if (a == foo)) is an error.
 * The way we capture this is:
 *  We generate the ajc$if method with an (a) parameter, we let eclipse do the proper
 * name binding.  We then, as a post pass (that we need to do anyway) look for the
 * used parameters.  If a is used, we signal an error because a was not one of the 
 * cflow variables. 
 * XXX we'll do this part after we do cflow
 * 
 * The IfPointcut pcd then generates itself always as a dynamic test, it has to
 * get the right parameters through any named pointcut references...
 */
public class IfPseudoToken extends PseudoToken {
    public Expression expr;
    public MethodDeclaration testMethod;
    private IfPointcut pointcut;
    
	public IfPseudoToken(
		Parser parser,
		Expression expr) {
		super(parser, "if", false);
		this.expr = expr;
	}
	
	public Pointcut maybeGetParsedPointcut() {
		pointcut = new IfPointcut(new ResolvedMember(Member.METHOD, TypeX.OBJECT, 0, "if_", "()V"), 0);
		return pointcut;
	}


	/**
	 * enclosingDec is either AdviceDeclaration or PointcutDeclaration
	 */
	public void postParse(TypeDeclaration typeDec, MethodDeclaration enclosingDec) {
//		typeDec.scope.problemReporter().signalError(sourceStart, sourceEnd,
//			"if pcd is not implemented in 1.1alpha1");
		//XXX need to implement correctly
		if (pointcut == null) return;
		testMethod = makeMethod(enclosingDec.compilationResult, enclosingDec);
		AstUtil.addMethodDeclaration(typeDec, testMethod);
	}


	//XXX static state bad
	private static int counter = 0;

	//XXX todo: make sure that errors in Arguments only get displayed once
	private MethodDeclaration makeMethod(CompilationResult result, MethodDeclaration enclosingDec) {
		MethodDeclaration ret = new IfMethodDeclaration(result, pointcut);
		ret.modifiers = AccStatic | AccFinal | AccPublic;
		ret.returnType = AstUtil.makeTypeReference(TypeBinding.BooleanBinding);
		ret.selector = ("ajc$if_" + counter++).toCharArray();
		ret.arguments = makeArguments(enclosingDec);
		ret.statements = new Statement[] {
			new ReturnStatement(expr, expr.sourceStart, expr.sourceEnd)
		};
		return ret;
	}

	private Argument[] makeArguments(MethodDeclaration enclosingDec) {
		Argument[] baseArguments = enclosingDec.arguments;
		int len = baseArguments.length;
		if (enclosingDec instanceof AdviceDeclaration) {
			len = ((AdviceDeclaration)enclosingDec).baseArgumentCount;
		}
		
		Argument[] ret = new Argument[len];
		for (int i=0; i < len; i ++) {
			Argument a = baseArguments[i];
			ret[i] = new Argument(a.name, AstUtil.makeLongPos(a.sourceStart, a.sourceEnd),
								a.type, Modifier.FINAL);
		}
		ret = AdviceDeclaration.addTjpArguments(ret);
		
		return ret;
	}

}