/* * @(#)$Id$ * * 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.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 String toString() { return("param("+_name+")"); } 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(Parser parser) { // Parse attributes name and select (if present) final String name = getAttribute("name"); if (name.length() > 0) { _name = parser.getQName(name); _name.clearDefaultNamespace(); } else { reportError(this, parser, ErrorMsg.NREQATTR_ERR, "name"); } // check whether variable/param of the same name is already in scope if (parser.lookupVariable(_name) != null) { ErrorMsg msg = new ErrorMsg(ErrorMsg.VARREDEF_ERR, _name, this); parser.reportError(Constants.ERROR, msg); } final String select = getAttribute("select"); if (select.length() > 0) { _select = parser.parseExpression(this, "select", null); } // Children must be parsed first -> static scoping parseChildren(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 if (parent instanceof Template) { _isLocal = true; ((Template)parent).hasParams(true); } } 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, Constants.EMPTYSTRING)); } } 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, Constants.EMPTYSTRING)); } } 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))); } } }