1 package org.apache.torque.generator.configuration.source; 2 3 /* 4 * Licensed to the Apache Software Foundation (ASF) under one 5 * or more contributor license agreements. See the NOTICE file 6 * distributed with this work for additional information 7 * regarding copyright ownership. The ASF licenses this file 8 * to you under the Apache License, Version 2.0 (the 9 * "License"); you may not use this file except in compliance 10 * with 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, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 */ 21 22 import java.io.ByteArrayInputStream; 23 import java.io.IOException; 24 import java.util.HashMap; 25 import java.util.Map; 26 27 import org.xml.sax.EntityResolver; 28 import org.xml.sax.InputSource; 29 import org.xml.sax.SAXException; 30 31 /** 32 * Resolves system Ids for schema files to the schema file content. 33 */ 34 public class EntityReferences implements EntityResolver 35 { 36 /** All known entity references. */ 37 private Map<String, byte[]> entityReferences 38 = new HashMap<String, byte[]>(); 39 40 /** 41 * Adds a new entity reference. 42 * 43 * @param systemId the systemId of the entity, not null. 44 * @param content the content of the entity, not null. 45 * 46 * @throws NullPointerException if systemId or content are null. 47 * @throws IllegalArgumentException if the systemId is already defined. 48 */ 49 public void addEntityReference(String systemId, byte[] content) 50 { 51 if (systemId == null) 52 { 53 throw new NullPointerException("systemId must not be null"); 54 } 55 if (content == null) 56 { 57 throw new NullPointerException("content must not be null"); 58 } 59 if (entityReferences.containsKey(systemId)) 60 { 61 throw new IllegalArgumentException("systemId is already defined"); 62 } 63 entityReferences.put(systemId, content); 64 } 65 66 /** 67 * Returns whether the given system id is known. 68 * 69 * @param systemId the system id to check. 70 * 71 * @return true if the system id can be resolved, false otherwise. 72 */ 73 public boolean containsSystemId(String systemId) 74 { 75 return entityReferences.containsKey(systemId); 76 } 77 78 /** 79 * Returns a copy of the entity reference map. 80 * 81 * @return a copy of the entity reference map. 82 */ 83 public Map<String, byte[]> getEntityReferences() 84 { 85 return new HashMap<String, byte[]>(entityReferences); 86 } 87 88 /** 89 * An implementation of the SAX <code>EntityResolver</code> 90 * interface to be called by the XML parser. If the systemId is known, 91 * the corresponding resource from the jar is returned. 92 * In all other cases, null is returned to indicate that the parser 93 * should open a regular connection to the systemId URI. 94 * 95 * @param publicId The public identifier of the external entity 96 * @param systemId The system identifier of the external entity 97 * @return An <code>InputSource</code> for the entity if the 98 * systemId is known, or null otherwise. 99 */ 100 public InputSource resolveEntity(String publicId, String systemId) 101 throws IOException, SAXException 102 { 103 104 byte[] content = entityReferences.get(systemId); 105 if (content == null) 106 { 107 return null; 108 } 109 return new InputSource(new ByteArrayInputStream(content)); 110 } 111 }