001/* 002 * Copyright 2002-2012 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.beans.factory.xml; 018 019import javax.xml.parsers.DocumentBuilder; 020import javax.xml.parsers.DocumentBuilderFactory; 021import javax.xml.parsers.ParserConfigurationException; 022 023import org.apache.commons.logging.Log; 024import org.apache.commons.logging.LogFactory; 025import org.w3c.dom.Document; 026import org.xml.sax.EntityResolver; 027import org.xml.sax.ErrorHandler; 028import org.xml.sax.InputSource; 029 030import org.springframework.util.xml.XmlValidationModeDetector; 031 032/** 033 * Spring's default {@link DocumentLoader} implementation. 034 * 035 * <p>Simply loads {@link Document documents} using the standard JAXP-configured 036 * XML parser. If you want to change the {@link DocumentBuilder} that is used to 037 * load documents, then one strategy is to define a corresponding Java system property 038 * when starting your JVM. For example, to use the Oracle {@link DocumentBuilder}, 039 * you might start your application like as follows: 040 * 041 * <pre code="class">java -Djavax.xml.parsers.DocumentBuilderFactory=oracle.xml.jaxp.JXDocumentBuilderFactory MyMainClass</pre> 042 * 043 * @author Rob Harrop 044 * @author Juergen Hoeller 045 * @since 2.0 046 */ 047public class DefaultDocumentLoader implements DocumentLoader { 048 049 /** 050 * JAXP attribute used to configure the schema language for validation. 051 */ 052 private static final String SCHEMA_LANGUAGE_ATTRIBUTE = "http://java.sun.com/xml/jaxp/properties/schemaLanguage"; 053 054 /** 055 * JAXP attribute value indicating the XSD schema language. 056 */ 057 private static final String XSD_SCHEMA_LANGUAGE = "http://www.w3.org/2001/XMLSchema"; 058 059 060 private static final Log logger = LogFactory.getLog(DefaultDocumentLoader.class); 061 062 063 /** 064 * Load the {@link Document} at the supplied {@link InputSource} using the standard JAXP-configured 065 * XML parser. 066 */ 067 @Override 068 public Document loadDocument(InputSource inputSource, EntityResolver entityResolver, 069 ErrorHandler errorHandler, int validationMode, boolean namespaceAware) throws Exception { 070 071 DocumentBuilderFactory factory = createDocumentBuilderFactory(validationMode, namespaceAware); 072 if (logger.isDebugEnabled()) { 073 logger.debug("Using JAXP provider [" + factory.getClass().getName() + "]"); 074 } 075 DocumentBuilder builder = createDocumentBuilder(factory, entityResolver, errorHandler); 076 return builder.parse(inputSource); 077 } 078 079 /** 080 * Create the {@link DocumentBuilderFactory} instance. 081 * @param validationMode the type of validation: {@link XmlValidationModeDetector#VALIDATION_DTD DTD} 082 * or {@link XmlValidationModeDetector#VALIDATION_XSD XSD}) 083 * @param namespaceAware whether the returned factory is to provide support for XML namespaces 084 * @return the JAXP DocumentBuilderFactory 085 * @throws ParserConfigurationException if we failed to build a proper DocumentBuilderFactory 086 */ 087 protected DocumentBuilderFactory createDocumentBuilderFactory(int validationMode, boolean namespaceAware) 088 throws ParserConfigurationException { 089 090 DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); 091 factory.setNamespaceAware(namespaceAware); 092 093 if (validationMode != XmlValidationModeDetector.VALIDATION_NONE) { 094 factory.setValidating(true); 095 if (validationMode == XmlValidationModeDetector.VALIDATION_XSD) { 096 // Enforce namespace aware for XSD... 097 factory.setNamespaceAware(true); 098 try { 099 factory.setAttribute(SCHEMA_LANGUAGE_ATTRIBUTE, XSD_SCHEMA_LANGUAGE); 100 } 101 catch (IllegalArgumentException ex) { 102 ParserConfigurationException pcex = new ParserConfigurationException( 103 "Unable to validate using XSD: Your JAXP provider [" + factory + 104 "] does not support XML Schema. Are you running on Java 1.4 with Apache Crimson? " + 105 "Upgrade to Apache Xerces (or Java 1.5) for full XSD support."); 106 pcex.initCause(ex); 107 throw pcex; 108 } 109 } 110 } 111 112 return factory; 113 } 114 115 /** 116 * Create a JAXP DocumentBuilder that this bean definition reader 117 * will use for parsing XML documents. Can be overridden in subclasses, 118 * adding further initialization of the builder. 119 * @param factory the JAXP DocumentBuilderFactory that the DocumentBuilder 120 * should be created with 121 * @param entityResolver the SAX EntityResolver to use 122 * @param errorHandler the SAX ErrorHandler to use 123 * @return the JAXP DocumentBuilder 124 * @throws ParserConfigurationException if thrown by JAXP methods 125 */ 126 protected DocumentBuilder createDocumentBuilder( 127 DocumentBuilderFactory factory, EntityResolver entityResolver, ErrorHandler errorHandler) 128 throws ParserConfigurationException { 129 130 DocumentBuilder docBuilder = factory.newDocumentBuilder(); 131 if (entityResolver != null) { 132 docBuilder.setEntityResolver(entityResolver); 133 } 134 if (errorHandler != null) { 135 docBuilder.setErrorHandler(errorHandler); 136 } 137 return docBuilder; 138 } 139 140}