/*
* @(#)$Id: AncestorPattern.java,v 1.8 2003/01/30 18:45:59 mkwan Exp $
*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 2001-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xalan" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 2001, Sun
* Microsystems., http://www.sun.com. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* @author Jacek Ambroziak
* @author Santiago Pericas-Geertsen
* @author Erwin Bolwidt <ejb@klomp.org>
*
*/
package org.apache.xalan.xsltc.compiler;
import org.apache.bcel.generic.BranchHandle;
import org.apache.bcel.generic.ConstantPoolGen;
import org.apache.bcel.generic.GOTO;
import org.apache.bcel.generic.IFEQ;
import org.apache.bcel.generic.ILOAD;
import org.apache.bcel.generic.INVOKEINTERFACE;
import org.apache.bcel.generic.ISTORE;
import org.apache.bcel.generic.InstructionHandle;
import org.apache.bcel.generic.InstructionList;
import org.apache.bcel.generic.LocalVariableGen;
import org.apache.xalan.xsltc.compiler.util.ClassGenerator;
import org.apache.xalan.xsltc.compiler.util.MethodGenerator;
import org.apache.xalan.xsltc.compiler.util.Type;
import org.apache.xalan.xsltc.compiler.util.TypeCheckError;
import org.apache.xalan.xsltc.compiler.util.Util;
final class AncestorPattern extends RelativePathPattern {
private final Pattern _left; // may be null
private final RelativePathPattern _right;
private InstructionHandle _loop;
public AncestorPattern(RelativePathPattern right) {
this(null, right);
}
public AncestorPattern(Pattern left, RelativePathPattern right) {
_left = left;
(_right = right).setParent(this);
if (left != null) {
left.setParent(this);
}
}
public InstructionHandle getLoopHandle() {
return _loop;
}
public void setParser(Parser parser) {
super.setParser(parser);
if (_left != null) {
_left.setParser(parser);
}
_right.setParser(parser);
}
public boolean isWildcard() {
//!!! can be wildcard
return false;
}
public StepPattern getKernelPattern() {
return _right.getKernelPattern();
}
public void reduceKernelPattern() {
_right.reduceKernelPattern();
}
public Type typeCheck(SymbolTable stable) throws TypeCheckError {
if (_left != null) {
_left.typeCheck(stable);
}
return _right.typeCheck(stable);
}
public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
InstructionHandle parent;
final ConstantPoolGen cpg = classGen.getConstantPool();
final InstructionList il = methodGen.getInstructionList();
/*
* The scope of this local var must be the entire method since
* a another pattern may decide to jump back into the loop
*/
final LocalVariableGen local =
methodGen.addLocalVariable2("app", Util.getJCRefType(NODE_SIG),
il.getEnd());
final org.apache.bcel.generic.Instruction loadLocal =
new ILOAD(local.getIndex());
final org.apache.bcel.generic.Instruction storeLocal =
new ISTORE(local.getIndex());
if (_right instanceof StepPattern) {
il.append(DUP);
il.append(storeLocal);
_right.translate(classGen, methodGen);
il.append(methodGen.loadDOM());
il.append(loadLocal);
}
else {
_right.translate(classGen, methodGen);
if (_right instanceof AncestorPattern) {
il.append(methodGen.loadDOM());
il.append(SWAP);
}
}
if (_left != null) {
final int getParent = cpg.addInterfaceMethodref(DOM_INTF,
GET_PARENT,
GET_PARENT_SIG);
parent = il.append(new INVOKEINTERFACE(getParent, 2));
il.append(DUP);
il.append(storeLocal);
_falseList.add(il.append(new IFEQ(null)));
il.append(loadLocal);
_left.translate(classGen, methodGen);
final SyntaxTreeNode p = getParent();
if (p == null || p instanceof Instruction ||
p instanceof TopLevelElement)
{
// do nothing
}
else {
il.append(loadLocal);
}
final BranchHandle exit = il.append(new GOTO(null));
_loop = il.append(methodGen.loadDOM());
il.append(loadLocal);
local.setEnd(_loop);
il.append(new GOTO(parent));
exit.setTarget(il.append(NOP));
_left.backPatchFalseList(_loop);
_trueList.append(_left._trueList);
}
else {
il.append(POP2);
}
/*
* If _right is an ancestor pattern, backpatch this pattern's false
* list to the loop that searches for more ancestors.
*/
if (_right instanceof AncestorPattern) {
final AncestorPattern ancestor = (AncestorPattern) _right;
_falseList.backPatch(ancestor.getLoopHandle()); // clears list
}
_trueList.append(_right._trueList);
_falseList.append(_right._falseList);
}
public String toString() {
return "AncestorPattern(" + _left + ", " + _right + ')';
}
}