/*
* @(#)$Id: Param.java,v 1.2 2001/05/02 10:24:59 morten Exp $
*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 2001 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
*
*/
package org.apache.xalan.xsltc.compiler;
import java.util.Vector;
import org.w3c.dom.*;
import org.apache.xalan.xsltc.compiler.util.Type;
import org.apache.xalan.xsltc.compiler.util.ReferenceType;
import de.fub.bytecode.generic.Instruction;
import de.fub.bytecode.generic.*;
import de.fub.bytecode.classfile.Field;
import org.apache.xalan.xsltc.compiler.util.*;
final class Param extends TopLevelElement {
private QName _name;
private boolean _isLocal; // true if the param is local
private Expression _select;
private Type _type;
// a JavaClass construct to refer to a JVM var
private LocalVariableGen _local;
// cached JavaClass instruction to push the contents of this var
private Instruction _loadInstruction;
// references to this variable (when local)
private Vector _refs = new Vector(2);
// to make sure parameter field is not added twice
private boolean _compiled = false;
public void display(int indent) {
indent(indent);
System.out.println("param " + _name);
if (_select != null) {
indent(indent + IndentIncrement);
System.out.println("select " + _select.toString());
}
displayContents(indent + IndentIncrement);
}
public void addReference(ParameterRef pref) {
_refs.addElement(pref);
}
public void removeReference(ParameterRef pref) {
_refs.remove(pref);
}
public void removeReference(ParameterRef pref, MethodGenerator methodGen) {
_refs.remove(pref);
if (_refs.isEmpty()) {
_local.setEnd(methodGen.getInstructionList().getEnd());
methodGen.removeLocalVariable(_local);
_refs = null;
_local = null;
}
}
public Instruction loadInstruction() {
final Instruction instr = _loadInstruction;
return instr != null
? instr : (_loadInstruction = _type.LOAD(_local.getIndex()));
}
public Type getType() {
return _type;
}
public boolean isLocal() {
return _isLocal;
}
public QName getName() {
return _name;
}
public void parseContents(Element element, Parser parser) {
// Parse attributes name and select (if present)
final String name = element.getAttribute("name");
if (name.length() > 0) {
_name = parser.getQName(name);
}
else {
reportError(element, parser, ErrorMsg.NREQATTR_ERR, "name");
}
// check whether variable/param of the same name is already in scope
if (parser.lookupVariable(_name) != null) {
ErrorMsg error = new ErrorMsg(ErrorMsg.VARREDEF_ERR, _name, this);
parser.addError(error);
}
final String select = element.getAttribute("select");
if (select.length() > 0) {
_select = parser.parseExpression(this, element, "select");
}
// Children must be parsed first -> static scoping
parseChildren(element, parser);
// Add a ref to this param to its enclosing construct
final SyntaxTreeNode parent = getParent();
if (parent instanceof Stylesheet) {
_isLocal = false;
((Stylesheet)parent).addParam(this);
//!! check for redef
parser.getSymbolTable().addParam(this);
}
else {
_isLocal = true;
parent.addParam(this);
}
}
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);
}
_type = Type.Reference;
return Type.Void;
}
public void compileResultTree(ClassGenerator classGen,
MethodGenerator methodGen) {
final ConstantPoolGen cpg = classGen.getConstantPool();
final InstructionList il = methodGen.getInstructionList();
// Save the current handler base on the stack
il.append(methodGen.loadHandler());
// Create new instance of DOM class (with 64 nodes)
final int init = cpg.addMethodref(DOM_IMPL, "<init>", "(I)V");
il.append(new NEW(cpg.addClass(DOM_IMPL)));
il.append(DUP);
il.append(DUP);
il.append(new PUSH(cpg, 64));
il.append(new INVOKESPECIAL(init));
// Overwrite old handler with DOM handler
final int getOutputDomBuilder =
cpg.addMethodref(DOM_IMPL,
"getOutputDomBuilder",
"()" + TRANSLET_OUTPUT_SIG);
il.append(new INVOKEVIRTUAL(getOutputDomBuilder));
il.append(DUP);
il.append(methodGen.storeHandler());
// Call startDocument on the new handler
il.append(methodGen.startDocument());
// Instantiate result tree fragment
translateContents(classGen, methodGen);
// Call endDocument on the new handler
il.append(methodGen.loadHandler());
il.append(methodGen.endDocument());
// Restore old handler base from stack
il.append(SWAP);
il.append(methodGen.storeHandler());
}
public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
final ConstantPoolGen cpg = classGen.getConstantPool();
final InstructionList il = methodGen.getInstructionList();
final String name = _name.getLocalPart(); // TODO: namespace ?
if (_compiled) return;
_compiled = true;
if (isLocal()) {
il.append(classGen.loadTranslet());
il.append(new PUSH(cpg, name));
if (_select == null) {
if (hasContents()) {
compileResultTree(classGen, methodGen);
}
else {
// If no select and no contents push the empty string
il.append(new PUSH(cpg, ""));
}
}
else {
_select.translate(classGen, methodGen);
_select.startResetIterator(classGen, methodGen);
}
// Call addParameter() from this class
final int addParameter = cpg.addMethodref(TRANSLET_CLASS,
ADD_PARAMETER,
ADD_PARAMETER_SIG);
il.append(new INVOKEVIRTUAL(addParameter));
if (_refs.isEmpty()) { // nobody uses the value
il.append(_type.POP());
_local = null;
}
else { // normal case
_local = methodGen.addLocalVariable2(name, _type.toJCType(),
il.getEnd());
// Cache the result of addParameter() in a local variable
il.append(_type.STORE(_local.getIndex()));
}
}
else {
String signature = _type.toSignature();
if (signature.equals(DOM_IMPL_SIG))
signature = classGen.getDOMClassSig();
classGen.addField(new Field(ACC_PUBLIC, cpg.addUtf8(name),
cpg.addUtf8(signature),
null, cpg.getConstantPool()));
il.append(classGen.loadTranslet());
il.append(DUP);
il.append(new PUSH(cpg, name));
if (_select == null) {
if (hasContents()) {
compileResultTree(classGen, methodGen);
}
else {
// If no select and no contents push the empty string
il.append(new PUSH(cpg, ""));
}
}
else {
_select.translate(classGen, methodGen);
_select.startResetIterator(classGen, methodGen);
}
// Call addParameter() from this class
il.append(new INVOKEVIRTUAL(cpg.addMethodref(TRANSLET_CLASS,
ADD_PARAMETER,
ADD_PARAMETER_SIG)));
// Cache the result of addParameter() in a field
il.append(new PUTFIELD(cpg.addFieldref(classGen.getClassName(),
name, signature)));
}
}
}