19f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson/* 29f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * Licensed to the Apache Software Foundation (ASF) under one 39f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * or more contributor license agreements. See the NOTICE file 49f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * distributed with this work for additional information 59f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * regarding copyright ownership. The ASF licenses this file 69f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * to you under the Apache License, Version 2.0 (the "License"); 79f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * you may not use this file except in compliance with the License. 89f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * You may obtain a copy of the License at 99f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * 109f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * http://www.apache.org/licenses/LICENSE-2.0 119f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * 129f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * Unless required by applicable law or agreed to in writing, software 139f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * distributed under the License is distributed on an "AS IS" BASIS, 149f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 159f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * See the License for the specific language governing permissions and 169f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * limitations under the License. 179f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson */ 189f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson/* 199f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * $Id: ExpressionVisitor.java 468637 2006-10-28 06:51:02Z minchau $ 209f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson */ 219f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonpackage org.apache.xalan.extensions; 229f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 239f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonimport org.apache.xalan.templates.StylesheetRoot; 249f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonimport org.apache.xpath.ExpressionOwner; 259f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonimport org.apache.xpath.XPathVisitor; 269f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonimport org.apache.xpath.functions.FuncExtFunction; 279f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonimport org.apache.xpath.functions.FuncExtFunctionAvailable; 289f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonimport org.apache.xpath.functions.Function; 299f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 309f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson/** 319f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * When {@link org.apache.xalan.processor.StylesheetHandler} creates 329f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * an {@link org.apache.xpath.XPath}, the ExpressionVisitor 339f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * visits the XPath expression. For any extension functions it 349f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * encounters, it instructs StylesheetRoot to register the 359f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * extension namespace. 369f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * 379f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * This mechanism is required to locate extension functions 389f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * that may be embedded within an expression. 399f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson */ 409f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonpublic class ExpressionVisitor extends XPathVisitor 419f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson{ 429f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson private StylesheetRoot m_sroot; 439f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 449f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson /** 459f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * The constructor sets the StylesheetRoot variable which 469f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * is used to register extension namespaces. 479f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * @param sroot the StylesheetRoot that is being constructed. 489f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson */ 499f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson public ExpressionVisitor (StylesheetRoot sroot) 509f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson { 519f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson m_sroot = sroot; 529f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson } 539f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 549f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson /** 559f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * If the function is an extension function, register the namespace. 569f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * 579f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * @param owner The current XPath object that owns the expression. 589f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * @param func The function currently being visited. 599f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * 609f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson * @return true to continue the visit in the subtree, if any. 619f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson */ 629f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson public boolean visitFunction(ExpressionOwner owner, Function func) 639f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson { 649f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (func instanceof FuncExtFunction) 659f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson { 669f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson String namespace = ((FuncExtFunction)func).getNamespace(); 679f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson m_sroot.getExtensionNamespacesManager().registerExtension(namespace); 689f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson } 699f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson else if (func instanceof FuncExtFunctionAvailable) 709f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson { 719f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson String arg = ((FuncExtFunctionAvailable)func).getArg0().toString(); 729f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (arg.indexOf(":") > 0) 739f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson { 749f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson String prefix = arg.substring(0,arg.indexOf(":")); 759f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson String namespace = this.m_sroot.getNamespaceForPrefix(prefix); 769f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson m_sroot.getExtensionNamespacesManager().registerExtension(namespace); 779f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson } 789f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson } 799f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson return true; 809f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson } 819f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 829f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson} 83