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	/*
	* Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
	*/
	/*
	* 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.
	*/

	package com.sun.org.apache.xalan.internal.xsltc.compiler;

	import com.sun.org.apache.bcel.internal.generic.ALOAD;
	import com.sun.org.apache.bcel.internal.generic.ASTORE;
	import com.sun.org.apache.bcel.internal.generic.CHECKCAST;
	import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
	import com.sun.org.apache.bcel.internal.generic.INVOKEINTERFACE;
	import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;
	import com.sun.org.apache.bcel.internal.generic.InstructionList;
	import com.sun.org.apache.bcel.internal.generic.LocalVariableGen;
	import com.sun.org.apache.bcel.internal.generic.PUSH;
	import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
	import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg;
	import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
	import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ReferenceType;
	import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
	import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
	import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Util;
	import com.sun.org.apache.xml.internal.utils.XML11Char;

	/**
	* @author Jacek Ambroziak
	* @author Santiago Pericas-Geertsen
	* @author Morten Jorgensen
	* @author John Howard <JohnH@schemasoft.com>
	*/
	final class WithParam extends Instruction {

	/**
	* Parameter's name.
	*/
	private QName _name;

	/**
	* The escaped qname of the with-param.
	*/
	protected String _escapedName;

	/**
	* Parameter's default value.
	*/
	private Expression _select;

	/**
	* Reference to JVM variable holding temporary result tree.
	*/
	private LocalVariableGen _domAdapter;

	/**
	* %OPT% This is set to true when the WithParam is used in a CallTemplate
	* for a simple named template. If this is true, the parameters are
	* passed to the named template through method arguments rather than
	* using the expensive Translet.addParameter() call.
	*/
	private boolean _doParameterOptimization = false;

	/**
	* Displays the contents of this element
	*/
	public void display(int indent) {
	indent(indent);
	Util.println("with-param " + _name);
	if (_select != null) {
	indent(indent + IndentIncrement);
	Util.println("select " + _select.toString());
	}
	displayContents(indent + IndentIncrement);
	}

	/**
	* Returns the escaped qname of the parameter
	*/
	public String getEscapedName() {
	return _escapedName;
	}

	/**
	* Return the name of this WithParam.
	*/
	public QName getName() {
	return _name;
	}

	/**
	* Set the name of the variable or paremeter. Escape all special chars.
	*/
	public void setName(QName name) {
	_name = name;
	_escapedName = Util.escape(name.getStringRep());
	}

	/**
	* Set the do parameter optimization flag
	*/
	public void setDoParameterOptimization(boolean flag) {
	_doParameterOptimization = flag;
	}

	/**
	* The contents of a <xsl:with-param> elements are either in the element's
	* 'select' attribute (this has precedence) or in the element body.
	*/
	public void parseContents(Parser parser) {
	final String name = getAttribute("name");
	if (name.length() > 0) {
	if (!XML11Char.isXML11ValidQName(name)) {
	ErrorMsg err = new ErrorMsg(ErrorMsg.INVALID_QNAME_ERR, name,
	this);
	parser.reportError(Constants.ERROR, err);
	}
	setName(parser.getQNameIgnoreDefaultNs(name));
	} else {
	reportError(this, parser, ErrorMsg.REQUIRED_ATTR_ERR, "name");
	}

	final String select = getAttribute("select");
	if (select.length() > 0) {
	_select = parser.parseExpression(this, "select", null);
	}

	parseChildren(parser);
	}

	/**
	* Type-check either the select attribute or the element body, depending
	* on which is in use.
	*/
	public Type typeCheck(SymbolTable stable) throws TypeCheckError {
	if (_select != null) {
	final Type tselect = _select.typeCheck(stable);
	if (tselect instanceof ReferenceType == false) {
	_select = new CastExpr(_select, Type.Reference);
	}
	} else {
	typeCheckContents(stable);
	}
	return Type.Void;
	}

	/**
	* Compile the value of the parameter, which is either in an expression in
	* a 'select' attribute, or in the with-param element's body
	*/
	public void translateValue(ClassGenerator classGen,
	MethodGenerator methodGen)
	{
	// Compile expression is 'select' attribute if present
	if (_select != null) {
	_select.translate(classGen, methodGen);
	_select.startIterator(classGen, methodGen);
	// If not, compile result tree from parameter body if present.
	// Store result tree into local variable for releasing it later
	} else if (hasContents()) {
	final InstructionList il = methodGen.getInstructionList();
	compileResultTree(classGen, methodGen);
	_domAdapter = methodGen.addLocalVariable2("@" + _escapedName,
	Type.ResultTree.toJCType(),
	il.getEnd());
	il.append(DUP);
	il.append(new ASTORE(_domAdapter.getIndex()));
	// If neither are present then store empty string in parameter slot
	} else {
	final ConstantPoolGen cpg = classGen.getConstantPool();
	final InstructionList il = methodGen.getInstructionList();
	il.append(new PUSH(cpg, Constants.EMPTYSTRING));
	}
	}

	/**
	* This code generates a sequence of bytecodes that call the
	* addParameter() method in AbstractTranslet. The method call will add
	* (or update) the parameter frame with the new parameter value.
	*/
	public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
	final ConstantPoolGen cpg = classGen.getConstantPool();
	final InstructionList il = methodGen.getInstructionList();

	// Translate the value and put it on the stack
	if (_doParameterOptimization) {
	translateValue(classGen, methodGen);
	return;
	}

	// Make name acceptable for use as field name in class
	String name = Util.escape(getEscapedName());

	// Load reference to the translet (method is in AbstractTranslet)
	il.append(classGen.loadTranslet());

	// Load the name of the parameter
	il.append(new PUSH(cpg, name)); // TODO: namespace ?
	// Generete the value of the parameter (use value in 'select' by def.)
	translateValue(classGen, methodGen);
	// Mark this parameter value is not being the default value
	il.append(new PUSH(cpg, false));
	// Pass the parameter to the template
	il.append(new INVOKEVIRTUAL(cpg.addMethodref(TRANSLET_CLASS,
	ADD_PARAMETER,
	ADD_PARAMETER_SIG)));
	il.append(POP); // cleanup stack
	}

	/**
	* Release the compiled result tree.
	*/
	public void releaseResultTree(ClassGenerator classGen,
	MethodGenerator methodGen)
	{
	if (_domAdapter != null) {
	final ConstantPoolGen cpg = classGen.getConstantPool();
	final InstructionList il = methodGen.getInstructionList();
	if (classGen.getStylesheet().callsNodeset() &&
	classGen.getDOMClass().equals(MULTI_DOM_CLASS))
	{
	final int removeDA =
	cpg.addMethodref(MULTI_DOM_CLASS, "removeDOMAdapter",
	"(" + DOM_ADAPTER_SIG + ")V");
	il.append(methodGen.loadDOM());
	il.append(new CHECKCAST(cpg.addClass(MULTI_DOM_CLASS)));
	il.append(new ALOAD(_domAdapter.getIndex()));
	il.append(new CHECKCAST(cpg.addClass(DOM_ADAPTER_CLASS)));
	il.append(new INVOKEVIRTUAL(removeDA));
	}
	final int release =
	cpg.addInterfaceMethodref(DOM_IMPL_CLASS, "release", "()V");
	il.append(new ALOAD(_domAdapter.getIndex()));
	il.append(new INVOKEINTERFACE(release, 1));
	_domAdapter.setEnd(il.getEnd());
	methodGen.removeLocalVariable(_domAdapter);
	_domAdapter = null;
	}
	}
	}

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