| /* |
| * 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. |
| */ |
| /* |
| * $Id$ |
| */ |
| |
| package org.apache.xalan.xsltc.compiler; |
| |
| import org.apache.xalan.xsltc.compiler.util.Type; |
| import org.apache.xalan.xsltc.compiler.util.TypeCheckError; |
| |
| /** |
| * @author Morten Jorgensen |
| * @author Santiago Pericas-Geertsen |
| */ |
| class VariableRefBase extends Expression { |
| |
| /** |
| * A reference to the associated variable. |
| */ |
| protected 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; |
| } |
| |
| /** |
| * If this variable reference is in a top-level element like |
| * another variable, param or key, add a dependency between |
| * that top-level element and the referenced variable. For |
| * example, |
| * |
| * <xsl:variable name="x" .../> |
| * <xsl:variable name="y" select="$x + 1"/> |
| * |
| * and assuming this class represents "$x", add a reference |
| * between variable y and variable x. |
| */ |
| public void addParentDependency() { |
| SyntaxTreeNode node = this; |
| while (node != null && node instanceof TopLevelElement == false) { |
| node = node.getParent(); |
| } |
| |
| TopLevelElement parent = (TopLevelElement) node; |
| if (parent != null) { |
| VariableBase var = _variable; |
| if (_variable._ignore) { |
| if (_variable instanceof Variable) { |
| var = parent.getSymbolTable() |
| .lookupVariable(_variable._name); |
| } else if (_variable instanceof Param) { |
| var = parent.getSymbolTable().lookupParam(_variable._name); |
| } |
| } |
| |
| parent.addDependency(var); |
| } |
| } |
| |
| /** |
| * 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); |
| } |
| } |
| |
| // 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(); |
| } |
| |
| // If in a top-level element, create dependency to the referenced var |
| addParentDependency(); |
| |
| // Return the type of the referenced variable |
| return _type; |
| } |
| |
| } |