| /* |
| * @(#)$Id$ |
| * |
| * 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.DOM; |
| import org.apache.xalan.xsltc.dom.Axis; |
| import org.apache.xalan.xsltc.compiler.util.Type; |
| |
| import org.apache.bcel.generic.Instruction; |
| import org.apache.bcel.generic.*; |
| import org.apache.xalan.xsltc.compiler.util.*; |
| |
| final class UnionPathExpr extends Expression { |
| |
| private final Expression _pathExpr; |
| private final Expression _rest; |
| private boolean _reverse = false; |
| |
| // linearization for top level UnionPathExprs |
| private Expression[] _components; |
| |
| public UnionPathExpr(Expression pathExpr, Expression rest) { |
| _pathExpr = pathExpr; |
| _rest = rest; |
| } |
| |
| public void setParser(Parser parser) { |
| super.setParser(parser); |
| // find all expressions in this Union |
| final Vector components = new Vector(); |
| flatten(components); |
| final int size = components.size(); |
| _components = (Expression[])components.toArray(new Expression[size]); |
| for (int i = 0; i < size; i++) { |
| _components[i].setParser(parser); |
| _components[i].setParent(this); |
| if (_components[i] instanceof Step) { |
| final Step step = (Step)_components[i]; |
| final int axis = step.getAxis(); |
| final int type = step.getNodeType(); |
| // Put attribute iterators first |
| if ((axis == Axis.ATTRIBUTE) || (type == DOM.ATTRIBUTE)) { |
| _components[i] = _components[0]; |
| _components[0] = step; |
| } |
| // Check if the union contains a reverse iterator |
| if (Axis.isReverse[axis]) _reverse = true; |
| } |
| } |
| // No need to reverse anything if another expression lies on top of this |
| if (getParent() instanceof Expression) _reverse = false; |
| } |
| |
| public Type typeCheck(SymbolTable stable) throws TypeCheckError { |
| final int length = _components.length; |
| for (int i = 0; i < length; i++) { |
| if (_components[i].typeCheck(stable) != Type.NodeSet) { |
| _components[i] = new CastExpr(_components[i], Type.NodeSet); |
| } |
| } |
| return _type = Type.NodeSet; |
| } |
| |
| public String toString() { |
| return "union(" + _pathExpr + ", " + _rest + ')'; |
| } |
| |
| private void flatten(Vector components) { |
| components.addElement(_pathExpr); |
| if (_rest != null) { |
| if (_rest instanceof UnionPathExpr) { |
| ((UnionPathExpr)_rest).flatten(components); |
| } |
| else { |
| components.addElement(_rest); |
| } |
| } |
| } |
| |
| public void translate(ClassGenerator classGen, MethodGenerator methodGen) { |
| final ConstantPoolGen cpg = classGen.getConstantPool(); |
| final InstructionList il = methodGen.getInstructionList(); |
| |
| final int init = cpg.addMethodref(UNION_ITERATOR_CLASS, |
| "<init>", |
| "("+DOM_INTF_SIG+")V"); |
| final int iter = cpg.addMethodref(UNION_ITERATOR_CLASS, |
| ADD_ITERATOR, |
| ADD_ITERATOR_SIG); |
| |
| // Create the UnionIterator and leave it on the stack |
| il.append(new NEW(cpg.addClass(UNION_ITERATOR_CLASS))); |
| il.append(DUP); |
| il.append(methodGen.loadDOM()); |
| il.append(new INVOKESPECIAL(init)); |
| |
| // Add the various iterators to the UnionIterator |
| final int length = _components.length; |
| for (int i = 0; i < length; i++) { |
| _components[i].translate(classGen, methodGen); |
| il.append(new INVOKEVIRTUAL(iter)); |
| } |
| |
| // Order the iterator only if strictly needed |
| if (_reverse) { |
| final int order = cpg.addInterfaceMethodref(DOM_INTF, |
| ORDER_ITERATOR, |
| ORDER_ITERATOR_SIG); |
| il.append(methodGen.loadDOM()); |
| il.append(SWAP); |
| il.append(methodGen.loadContextNode()); |
| il.append(new INVOKEINTERFACE(order, 3)); |
| |
| } |
| } |
| } |