/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* $Id: ParentPattern.java 468650 2006-10-28 07:03:30Z minchau $
*/
package org.apache.xalan.xsltc.compiler;
import org.apache.bcel.generic.ConstantPoolGen;
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;
/**
* @author Jacek Ambroziak
* @author Santiago Pericas-Geertsen
*/
final class ParentPattern extends RelativePathPattern {
private final Pattern _left;
private final RelativePathPattern _right;
public ParentPattern(Pattern left, RelativePathPattern right) {
(_left = left).setParent(this);
(_right = right).setParent(this);
}
public void setParser(Parser parser) {
super.setParser(parser);
_left.setParser(parser);
_right.setParser(parser);
}
public boolean isWildcard() {
return false;
}
public StepPattern getKernelPattern() {
return _right.getKernelPattern();
}
public void reduceKernelPattern() {
_right.reduceKernelPattern();
}
public Type typeCheck(SymbolTable stable) throws TypeCheckError {
_left.typeCheck(stable);
return _right.typeCheck(stable);
}
public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
final ConstantPoolGen cpg = classGen.getConstantPool();
final InstructionList il = methodGen.getInstructionList();
final LocalVariableGen local =
methodGen.addLocalVariable2("ppt",
Util.getJCRefType(NODE_SIG),
null);
final org.apache.bcel.generic.Instruction loadLocal =
new ILOAD(local.getIndex());
final org.apache.bcel.generic.Instruction storeLocal =
new ISTORE(local.getIndex());
if (_right.isWildcard()) {
il.append(methodGen.loadDOM());
il.append(SWAP);
}
else if (_right instanceof StepPattern) {
il.append(DUP);
local.setStart(il.append(storeLocal));
_right.translate(classGen, methodGen);
il.append(methodGen.loadDOM());
local.setEnd(il.append(loadLocal));
}
else {
_right.translate(classGen, methodGen);
if (_right instanceof AncestorPattern) {
il.append(methodGen.loadDOM());
il.append(SWAP);
}
}
final int getParent = cpg.addInterfaceMethodref(DOM_INTF,
GET_PARENT,
GET_PARENT_SIG);
il.append(new INVOKEINTERFACE(getParent, 2));
final SyntaxTreeNode p = getParent();
if (p == null || p instanceof Instruction ||
p instanceof TopLevelElement)
{
_left.translate(classGen, methodGen);
}
else {
il.append(DUP);
InstructionHandle storeInst = il.append(storeLocal);
if (local.getStart() == null) {
local.setStart(storeInst);
}
_left.translate(classGen, methodGen);
il.append(methodGen.loadDOM());
local.setEnd(il.append(loadLocal));
}
methodGen.removeLocalVariable(local);
/*
* If _right is an ancestor pattern, backpatch _left false
* list to the loop that searches for more ancestors.
*/
if (_right instanceof AncestorPattern) {
final AncestorPattern ancestor = (AncestorPattern) _right;
_left.backPatchFalseList(ancestor.getLoopHandle()); // clears list
}
_trueList.append(_right._trueList.append(_left._trueList));
_falseList.append(_right._falseList.append(_left._falseList));
}
public String toString() {
return "Parent(" + _left + ", " + _right + ')';
}
}