1/* 2 * reserved comment block 3 * DO NOT REMOVE OR ALTER! 4 */ 5/* 6 * Licensed to the Apache Software Foundation (ASF) under one or more 7 * contributor license agreements. See the NOTICE file distributed with 8 * this work for additional information regarding copyright ownership. 9 * The ASF licenses this file to You under the Apache License, Version 2.0 10 * (the "License"); you may not use this file except in compliance with 11 * the License. You may obtain a copy of the License at 12 * 13 * http://www.apache.org/licenses/LICENSE-2.0 14 * 15 * Unless required by applicable law or agreed to in writing, software 16 * distributed under the License is distributed on an "AS IS" BASIS, 17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 18 * See the License for the specific language governing permissions and 19 * limitations under the License. 20 */ 21 22package com.sun.org.apache.xpath.internal.compiler; 23 24import javax.xml.transform.TransformerException; 25 26import com.sun.org.apache.xpath.internal.functions.Function; 27import com.sun.org.apache.xalan.internal.utils.ObjectFactory; 28import com.sun.org.apache.xalan.internal.utils.ConfigurationError; 29 30/** 31 * Lazy load of functions into the function table as needed, so we don't 32 * have to load all the functions allowed in XPath and XSLT on startup. 33 * @xsl.usage advanced 34 */ 35public class FuncLoader 36{ 37 38 /** The function ID, which may correspond to one of the FUNC_XXX values 39 * found in {@link com.sun.org.apache.xpath.internal.compiler.FunctionTable}, but may 40 * be a value installed by an external module. */ 41 private int m_funcID; 42 43 /** The class name of the function. Must not be null. */ 44 private String m_funcName; 45 46 /** 47 * Get the local class name of the function class. If function name does 48 * not have a '.' in it, it is assumed to be relative to 49 * 'com.sun.org.apache.xpath.internal.functions'. 50 * 51 * @return The class name of the {com.sun.org.apache.xpath.internal.functions.Function} class. 52 */ 53 public String getName() 54 { 55 return m_funcName; 56 } 57 58 /** 59 * Construct a function loader 60 * 61 * @param funcName The class name of the {com.sun.org.apache.xpath.internal.functions.Function} 62 * class, which, if it does not have a '.' in it, is assumed to 63 * be relative to 'com.sun.org.apache.xpath.internal.functions'. 64 * @param funcID The function ID, which may correspond to one of the FUNC_XXX 65 * values found in {@link com.sun.org.apache.xpath.internal.compiler.FunctionTable}, but may 66 * be a value installed by an external module. 67 */ 68 public FuncLoader(String funcName, int funcID) 69 { 70 71 super(); 72 73 m_funcID = funcID; 74 m_funcName = funcName; 75 } 76 77 /** 78 * Get a Function instance that this instance is liaisoning for. 79 * 80 * @return non-null reference to Function derivative. 81 * 82 * @throws javax.xml.transform.TransformerException if ClassNotFoundException, 83 * IllegalAccessException, or InstantiationException is thrown. 84 */ 85 Function getFunction() throws TransformerException 86 { 87 try 88 { 89 String className = m_funcName; 90 if (className.indexOf(".") < 0) { 91 className = "com.sun.org.apache.xpath.internal.functions." + className; 92 } 93 //hack for loading only built-in function classes. 94 String subString = className.substring(0,className.lastIndexOf('.')); 95 if(!(subString.equals ("com.sun.org.apache.xalan.internal.templates") || 96 subString.equals ("com.sun.org.apache.xpath.internal.functions"))) { 97 throw new TransformerException("Application can't install his own xpath function."); 98 } 99 100 return (Function) ObjectFactory.newInstance(className, true); 101 102 } 103 catch (ConfigurationError e) 104 { 105 throw new TransformerException(e.getException()); 106 } 107 } 108} 109