SerializerFactory.java revision 1188:86157a0bf14f
1/* 2 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved. 3 */ 4/* 5 * Licensed to the Apache Software Foundation (ASF) under one or more 6 * contributor license agreements. See the NOTICE file distributed with 7 * this work for additional information regarding copyright ownership. 8 * The ASF licenses this file to You under the Apache License, Version 2.0 9 * (the "License"); you may not use this file except in compliance with 10 * the License. You may obtain a copy of the License at 11 * 12 * http://www.apache.org/licenses/LICENSE-2.0 13 * 14 * Unless required by applicable law or agreed to in writing, software 15 * distributed under the License is distributed on an "AS IS" BASIS, 16 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 17 * See the License for the specific language governing permissions and 18 * limitations under the License. 19 */ 20 21package com.sun.org.apache.xml.internal.serializer; 22 23import java.util.Properties; 24 25import javax.xml.transform.OutputKeys; 26 27import com.sun.org.apache.xml.internal.serializer.utils.MsgKey; 28import com.sun.org.apache.xml.internal.serializer.utils.Utils; 29import com.sun.org.apache.xalan.internal.utils.ObjectFactory; 30import org.xml.sax.ContentHandler; 31 32/** 33 * This class is a public API, it is a factory for creating serializers. 34 * 35 * The properties object passed to the getSerializer() method should be created by 36 * the OutputPropertiesFactory. Although the properties object 37 * used to create a serializer does not need to be obtained 38 * from OutputPropertiesFactory, 39 * using this factory ensures that the default key/value properties 40 * are set for the given output "method". 41 * 42 * <p> 43 * The standard property keys supported are: "method", "version", "encoding", 44 * "omit-xml-declaration", "standalone", doctype-public", 45 * "doctype-system", "cdata-section-elements", "indent", "media-type". 46 * These property keys and their values are described in the XSLT recommendation, 47 * see {@link <a href="http://www.w3.org/TR/1999/REC-xslt-19991116"> XSLT 1.0 recommendation</a>} 48 * 49 * <p> 50 * The value of the "cdata-section-elements" property key is a whitespace 51 * separated list of elements. If the element is in a namespace then 52 * value is passed in this format: {uri}localName 53 * 54 * <p> 55 * The non-standard property keys supported are defined in {@link OutputPropertiesFactory}. 56 * 57 * @see OutputPropertiesFactory 58 * @see Method 59 * @see Serializer 60 */ 61public final class SerializerFactory 62{ 63 /** 64 * This constructor is private just to prevent the creation of such an object. 65 */ 66 67 private SerializerFactory() { 68 69 } 70 71 /** 72 * Returns a serializer for the specified output method. The output method 73 * is specified by the value of the property associated with the "method" key. 74 * If no implementation exists that supports the specified output method 75 * an exception of some type will be thrown. 76 * For a list of the output "method" key values see {@link Method}. 77 * 78 * @param format The output format, minimally the "method" property must be set. 79 * @return A suitable serializer. 80 * @throws IllegalArgumentException if method is 81 * null or an appropriate serializer can't be found 82 * @throws Exception if the class for the serializer is found but does not 83 * implement ContentHandler. 84 * @throws WrappedRuntimeException if an exception is thrown while trying to find serializer 85 */ 86 public static Serializer getSerializer(Properties format) 87 { 88 Serializer ser; 89 90 try 91 { 92 String method = format.getProperty(OutputKeys.METHOD); 93 94 if (method == null) { 95 String msg = Utils.messages.createMessage( 96 MsgKey.ER_FACTORY_PROPERTY_MISSING, 97 new Object[] { OutputKeys.METHOD}); 98 throw new IllegalArgumentException(msg); 99 } 100 101 String className = 102 format.getProperty(OutputPropertiesFactory.S_KEY_CONTENT_HANDLER); 103 104 105 if (null == className) 106 { 107 // Missing Content Handler property, load default using OutputPropertiesFactory 108 Properties methodDefaults = 109 OutputPropertiesFactory.getDefaultMethodProperties(method); 110 className = 111 methodDefaults.getProperty(OutputPropertiesFactory.S_KEY_CONTENT_HANDLER); 112 if (null == className) { 113 String msg = Utils.messages.createMessage( 114 MsgKey.ER_FACTORY_PROPERTY_MISSING, 115 new Object[] { OutputPropertiesFactory.S_KEY_CONTENT_HANDLER}); 116 throw new IllegalArgumentException(msg); 117 } 118 119 } 120 121 122 123 Class cls = ObjectFactory.findProviderClass(className, true); 124 125 // _serializers.put(method, cls); 126 127 Object obj = cls.getConstructor().newInstance(); 128 129 if (obj instanceof SerializationHandler) 130 { 131 // this is one of the supplied serializers 132 ser = (Serializer) obj; 133 ser.setOutputFormat(format); 134 } 135 else 136 { 137 /* 138 * This must be a user defined Serializer. 139 * It had better implement ContentHandler. 140 */ 141 if (obj instanceof ContentHandler) 142 { 143 144 /* 145 * The user defined serializer defines ContentHandler, 146 * but we need to wrap it with ToXMLSAXHandler which 147 * will collect SAX-like events and emit true 148 * SAX ContentHandler events to the users handler. 149 */ 150 className = SerializerConstants.DEFAULT_SAX_SERIALIZER; 151 cls = ObjectFactory.findProviderClass(className, true); 152 SerializationHandler sh = 153 (SerializationHandler) cls.getConstructor().newInstance(); 154 sh.setContentHandler( (ContentHandler) obj); 155 sh.setOutputFormat(format); 156 157 ser = sh; 158 } 159 else 160 { 161 // user defined serializer does not implement 162 // ContentHandler, ... very bad 163 throw new Exception( 164 Utils.messages.createMessage( 165 MsgKey.ER_SERIALIZER_NOT_CONTENTHANDLER, 166 new Object[] { className})); 167 } 168 169 } 170 } 171 catch (Exception e) 172 { 173 throw new com.sun.org.apache.xml.internal.serializer.utils.WrappedRuntimeException(e); 174 } 175 176 // If we make it to here ser is not null. 177 return ser; 178 } 179} 180