| /* |
| * @(#)$Id$ |
| * |
| * 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 Morten Jorgensen |
| * @author Santiago Pericas-Geertsen |
| * |
| */ |
| |
| package org.apache.xalan.xsltc.compiler; |
| |
| import org.apache.xalan.xsltc.compiler.util.Type; |
| import org.apache.bcel.generic.*; |
| import org.apache.xalan.xsltc.compiler.util.*; |
| |
| class VariableRefBase extends Expression { |
| |
| /** |
| * A reference to the associated variable. |
| */ |
| protected final VariableBase _variable; |
| |
| /** |
| * A reference to the enclosing expression/instruction for which a |
| * closure is needed (Predicate, Number or Sort). |
| */ |
| protected Closure _closure = null; |
| |
| public VariableRefBase(VariableBase variable) { |
| _variable = variable; |
| variable.addReference(this); |
| } |
| |
| public VariableRefBase() { |
| _variable = null; |
| } |
| |
| /** |
| * Returns a reference to the associated variable |
| */ |
| public VariableBase getVariable() { |
| return _variable; |
| } |
| |
| /** |
| * Returns a reference to any parent variable |
| */ |
| public VariableBase findParentVariable() { |
| SyntaxTreeNode node = this; |
| while (node != null && !(node instanceof VariableBase)) { |
| node = node.getParent(); |
| } |
| return (VariableBase) node; |
| } |
| |
| /** |
| * Two variable references are deemed equal if they refer to the |
| * same variable. |
| */ |
| public boolean equals(Object obj) { |
| try { |
| return (_variable == ((VariableRefBase) obj)._variable); |
| } |
| catch (ClassCastException e) { |
| return false; |
| } |
| } |
| |
| /** |
| * Returns a string representation of this variable reference on the |
| * format 'variable-ref(<var-name>)'. |
| * @return Variable reference description |
| */ |
| public String toString() { |
| return "variable-ref("+_variable.getName()+'/'+_variable.getType()+')'; |
| } |
| |
| public Type typeCheck(SymbolTable stable) |
| throws TypeCheckError |
| { |
| // Returned cached type if available |
| if (_type != null) return _type; |
| |
| // Find nearest closure to add a variable reference |
| if (_variable.isLocal()) { |
| SyntaxTreeNode node = getParent(); |
| do { |
| if (node instanceof Closure) { |
| _closure = (Closure) node; |
| break; |
| } |
| if (node instanceof TopLevelElement) { |
| break; // way up in the tree |
| } |
| node = node.getParent(); |
| } while (node != null); |
| |
| if (_closure != null) { |
| _closure.addVariable(this); |
| } |
| } |
| |
| // Insert a dependency link from one variable to another |
| VariableBase parent = findParentVariable(); |
| if (parent != null) parent.addDependency(_variable); |
| |
| // Attempt to get the cached variable type |
| _type = _variable.getType(); |
| |
| // If that does not work we must force a type-check (this is normally |
| // only needed for globals in included/imported stylesheets |
| if (_type == null) { |
| _variable.typeCheck(stable); |
| _type = _variable.getType(); |
| } |
| |
| // Return the type of the referenced variable |
| return _type; |
| } |
| |
| } |