1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 /* 19 * $Id: ElemUnknown.java 468643 2006-10-28 06:56:03Z minchau $ 20 */ 21 package org.apache.xalan.templates; 22 23 import javax.xml.transform.TransformerException; 24 25 import org.apache.xalan.transformer.TransformerImpl; 26 27 28 /** 29 * Implement an unknown element 30 * @xsl.usage advanced 31 */ 32 public class ElemUnknown extends ElemLiteralResult 33 { 34 static final long serialVersionUID = -4573981712648730168L; 35 36 /** 37 * Get an int constant identifying the type of element. 38 * @see org.apache.xalan.templates.Constants 39 * 40 *@return The token ID for this element 41 */ getXSLToken()42 public int getXSLToken() 43 { 44 return Constants.ELEMNAME_UNDEFINED; 45 } 46 47 /** 48 * Execute the fallbacks when an extension is not available. 49 * 50 * @param transformer non-null reference to the the current transform-time state. 51 * 52 * @throws TransformerException 53 */ executeFallbacks( TransformerImpl transformer)54 private void executeFallbacks( 55 TransformerImpl transformer) 56 throws TransformerException 57 { 58 for (ElemTemplateElement child = m_firstChild; child != null; 59 child = child.m_nextSibling) 60 { 61 if (child.getXSLToken() == Constants.ELEMNAME_FALLBACK) 62 { 63 try 64 { 65 transformer.pushElemTemplateElement(child); 66 ((ElemFallback) child).executeFallback(transformer); 67 } 68 finally 69 { 70 transformer.popElemTemplateElement(); 71 } 72 } 73 } 74 75 } 76 77 /** 78 * Return true if this extension element has a <xsl:fallback> child element. 79 * 80 * @return true if this extension element has a <xsl:fallback> child element. 81 */ hasFallbackChildren()82 private boolean hasFallbackChildren() 83 { 84 for (ElemTemplateElement child = m_firstChild; child != null; 85 child = child.m_nextSibling) 86 { 87 if (child.getXSLToken() == Constants.ELEMNAME_FALLBACK) 88 return true; 89 } 90 91 return false; 92 } 93 94 95 /** 96 * Execute an unknown element. 97 * Execute fallback if fallback child exists or do nothing 98 * 99 * @param transformer non-null reference to the the current transform-time state. 100 * 101 * @throws TransformerException 102 */ execute(TransformerImpl transformer)103 public void execute(TransformerImpl transformer) 104 throws TransformerException 105 { 106 107 108 try { 109 110 if (hasFallbackChildren()) { 111 executeFallbacks(transformer); 112 } else { 113 // do nothing 114 } 115 116 } catch (TransformerException e) { 117 transformer.getErrorListener().fatalError(e); 118 } 119 } 120 121 } 122