content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   * 
   *      http://www.apache.org/licenses/LICENSE-2.0
   * 
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package mf.org.apache.xerces.util;
  
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.Reader;
  import java.io.StringReader;
  
  import mf.org.apache.xerces.xni.XMLResourceIdentifier;
  import mf.org.apache.xerces.xni.XNIException;
  import mf.org.apache.xerces.xni.grammars.XMLGrammarDescription;
  import mf.org.apache.xerces.xni.parser.XMLEntityResolver;
  import mf.org.apache.xerces.xni.parser.XMLInputSource;
  import mf.org.w3c.dom.ls.LSInput;
  import mf.org.w3c.dom.ls.LSResourceResolver;
  
  
  /**
   * This class wraps DOM entity resolver to XNI entity resolver.
   *
   * @author Gopal Sharma, SUN MicroSystems Inc.
   * @author Elena Litani, IBM
   * @author Ramesh Mandava, Sun Microsystems
   * @version $Id: DOMEntityResolverWrapper.java 699892 2008-09-28 21:08:27Z mrglavas $
   * @see LSResourceResolver
   */
  public class DOMEntityResolverWrapper
          implements XMLEntityResolver {
  
      //
      // Data
      //
  
      /**
       * XML 1.0 type constant according to DOM L3 LS CR spec "http://www.w3.org/TR/2003/CR-DOM-Level-3-LS-20031107"
       */
      private static final String XML_TYPE = "http://www.w3.org/TR/REC-xml";
  
      /**
       * XML Schema constant according to DOM L3 LS CR spec "http://www.w3.org/TR/2003/CR-DOM-Level-3-LS-20031107"
       */
      private static final String XSD_TYPE = "http://www.w3.org/2001/XMLSchema";
  
      /**
       * The DOM entity resolver.
       */
      protected LSResourceResolver fEntityResolver;
  
      //
      // Constructors
      //
  
      /**
       * Default constructor.
       */
      public DOMEntityResolverWrapper() {
      }
  
      /**
       * Wraps the specified DOM entity resolver.
       */
      public DOMEntityResolverWrapper(LSResourceResolver entityResolver) {
          setEntityResolver(entityResolver);
      } // LSResourceResolver
  
      //
      // Public methods
      //
  
      /**
       * Returns the DOM entity resolver.
       */
      public LSResourceResolver getEntityResolver() {
          return fEntityResolver;
      } // getEntityResolver():LSResourceResolver
  
      /**
       * Sets the DOM entity resolver.
       */
      public void setEntityResolver(LSResourceResolver entityResolver) {
          fEntityResolver = entityResolver;
      } // setEntityResolver(LSResourceResolver)
  
      //
      // XMLEntityResolver methods
      //
  
      /**
       * Resolves an external parsed entity. If the entity cannot be
       * resolved, this method should return null.
       *
       * @param resourceIdentifier description of the resource to be revsoved
       * @throws XNIException Thrown on general error.
       * @throws IOException  Thrown if resolved entity stream cannot be
       *                      opened or some other i/o error occurs.
       */
      @Override
      public XMLInputSource resolveEntity(XMLResourceIdentifier resourceIdentifier)
              throws XNIException, IOException {
          // resolve entity using DOM entity resolver
          if (fEntityResolver != null) {
              // For entity resolution the type of the resource would be  XML TYPE
              // DOM L3 LS spec mention only the XML 1.0 recommendation right now
              LSInput inputSource =
                      resourceIdentifier == null
                              ? fEntityResolver.resolveResource(
                              null,
                              null,
                              null,
                              null,
                              null)
                              : fEntityResolver.resolveResource(
                              getType(resourceIdentifier),
                              resourceIdentifier.getNamespace(),
                              resourceIdentifier.getPublicId(),
                              resourceIdentifier.getLiteralSystemId(),
                              resourceIdentifier.getBaseSystemId());
              if (inputSource != null) {
                  String publicId = inputSource.getPublicId();
                  String systemId = inputSource.getSystemId();
                  String baseSystemId = inputSource.getBaseURI();
                  InputStream byteStream = inputSource.getByteStream();
                  Reader charStream = inputSource.getCharacterStream();
                  String encoding = inputSource.getEncoding();
                  String data = inputSource.getStringData();
  
                  /**
                   * An LSParser looks at inputs specified in LSInput in
                   * the following order: characterStream, byteStream,
                   * stringData, systemId, publicId.
                   */
                  XMLInputSource xmlInputSource =
                          new XMLInputSource(publicId, systemId, baseSystemId);
  
                  if (charStream != null) {
                      xmlInputSource.setCharacterStream(charStream);
                  } else if (byteStream != null) {
                      xmlInputSource.setByteStream(byteStream);
                  } else if (data != null && data.length() != 0) {
                      xmlInputSource.setCharacterStream(new StringReader(data));
                  }
                  xmlInputSource.setEncoding(encoding);
                  return xmlInputSource;
              }
          }
  
          // unable to resolve entity
          return null;
  
      } // resolveEntity(String,String,String):XMLInputSource
  
      /**
       * Determines the type of resource being resolved
       **/
      private String getType(XMLResourceIdentifier resourceIdentifier) {
          if (resourceIdentifier instanceof XMLGrammarDescription) {
              XMLGrammarDescription desc = (XMLGrammarDescription) resourceIdentifier;
              if (XMLGrammarDescription.XML_SCHEMA.equals(desc.getGrammarType())) {
                  return XSD_TYPE;
              }
          }
          return XML_TYPE;
      } // getType(XMLResourceIdentifier):String
  
  } // DOMEntityResolverWrapper
  