/*
* @(#)$Id: ProcessingInstructionPattern.java,v 1.4 2003/01/30 18:46:01 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 Morten Jorgensen
*
*/
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.IF_ICMPEQ;
import org.apache.bcel.generic.INVOKEINTERFACE;
import org.apache.bcel.generic.INVOKEVIRTUAL;
import org.apache.bcel.generic.InstructionHandle;
import org.apache.bcel.generic.InstructionList;
import org.apache.bcel.generic.PUSH;
import org.apache.xalan.xsltc.DOM;
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.dom.Axis;
final class ProcessingInstructionPattern extends StepPattern {
private String _name = null;
private boolean _typeChecked = false;
/**
* Handles calls with no parameter (current node is implicit parameter).
*/
public ProcessingInstructionPattern(String name) {
super(Axis.CHILD, DOM.PROCESSING_INSTRUCTION, null);
_name = name;
//if (_name.equals("*")) _typeChecked = true; no wildcard allowed!
}
/**
*
*/
public String toString() {
if (_predicates == null)
return "processing-instruction("+_name+")";
else
return "processing-instruction("+_name+")"+_predicates;
}
public void reduceKernelPattern() {
_typeChecked = true;
}
public boolean isWildcard() {
return false;
}
public Type typeCheck(SymbolTable stable) throws TypeCheckError {
if (hasPredicates()) {
// Type check all the predicates (e -> position() = e)
final int n = _predicates.size();
for (int i = 0; i < n; i++) {
final Predicate pred = (Predicate)_predicates.elementAt(i);
pred.typeCheck(stable);
}
}
return Type.NodeSet;
}
public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
final ConstantPoolGen cpg = classGen.getConstantPool();
final InstructionList il = methodGen.getInstructionList();
// context node is on the stack
int gname = cpg.addInterfaceMethodref(DOM_INTF,
"getNodeName",
"(I)Ljava/lang/String;");
int cmp = cpg.addMethodref(STRING_CLASS,
"equals", "(Ljava/lang/Object;)Z");
// Push current node on the stack
il.append(methodGen.loadCurrentNode());
il.append(SWAP);
// Overwrite current node with matching node
il.append(methodGen.storeCurrentNode());
// If pattern not reduced then check kernel
if (!_typeChecked) {
il.append(methodGen.loadCurrentNode());
final int getType = cpg.addInterfaceMethodref(DOM_INTF,
"getType", "(I)I");
il.append(methodGen.loadDOM());
il.append(methodGen.loadCurrentNode());
il.append(new INVOKEINTERFACE(getType, 2));
il.append(new PUSH(cpg, DOM.PROCESSING_INSTRUCTION));
_falseList.add(il.append(new IF_ICMPEQ(null)));
}
// Load the requested processing instruction name
il.append(new PUSH(cpg, _name));
// Load the current processing instruction's name
il.append(methodGen.loadDOM());
il.append(methodGen.loadCurrentNode());
il.append(new INVOKEINTERFACE(gname, 2));
// Compare the two strings
il.append(new INVOKEVIRTUAL(cmp));
_falseList.add(il.append(new IFEQ(null)));
// Compile the expressions within the predicates
if (hasPredicates()) {
final int n = _predicates.size();
for (int i = 0; i < n; i++) {
Predicate pred = (Predicate)_predicates.elementAt(i);
Expression exp = pred.getExpr();
exp.translateDesynthesized(classGen, methodGen);
_trueList.append(exp._trueList);
_falseList.append(exp._falseList);
}
}
// Backpatch true list and restore current iterator/node
InstructionHandle restore;
restore = il.append(methodGen.storeCurrentNode());
backPatchTrueList(restore);
BranchHandle skipFalse = il.append(new GOTO(null));
// Backpatch false list and restore current iterator/node
restore = il.append(methodGen.storeCurrentNode());
backPatchFalseList(restore);
_falseList.add(il.append(new GOTO(null)));
// True list falls through
skipFalse.setTarget(il.append(NOP));
}
}