content: /*
   * Copyright (c) 2000, 2005, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  // SAX entity resolver.
  // http://www.saxproject.org
  // No warranty; no copyright -- use this as you will.
  // $Id: EntityResolver.java,v 1.2 2004/11/03 22:44:52 jsuttor Exp $
  
  package org.xml.sax;
  
  import org.xml.sax.InputSource;
  import org.xml.sax.SAXException;
  
  import java.io.IOException;
  
  
  /**
   * Basic interface for resolving entities.
   *
   * <blockquote>
   * <em>This module, both source code and documentation, is in the
   * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
   * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
   * for further information.
   * </blockquote>
   *
   * <p>If a SAX application needs to implement customized handling
   * for external entities, it must implement this interface and
   * register an instance with the SAX driver using the
   * {@link org.xml.sax.XMLReader#setEntityResolver setEntityResolver}
   * method.</p>
   *
   * <p>The XML reader will then allow the application to intercept any
   * external entities (including the external DTD subset and external
   * parameter entities, if any) before including them.</p>
   *
   * <p>Many SAX applications will not need to implement this interface,
   * but it will be especially useful for applications that build
   * XML documents from databases or other specialised input sources,
   * or for applications that use URI types other than URLs.</p>
   *
   * <p>The following resolver would provide the application
   * with a special character stream for the entity with the system
   * identifier "http://www.myhost.com/today":</p>
   *
   * <pre>
   * import org.xml.sax.EntityResolver;
   * import org.xml.sax.InputSource;
   *
   * public class MyResolver implements EntityResolver {
   *   public InputSource resolveEntity (String publicId, String systemId)
   *   {
   *     if (systemId.equals("http://www.myhost.com/today")) {
   *              // return a special input source
   *       MyReader reader = new MyReader();
   *       return new InputSource(reader);
   *     } else {
   *              // use the default behaviour
   *       return null;
   *     }
   *   }
   * }
   * </pre>
   *
   * <p>The application can also use this interface to redirect system
   * identifiers to local URIs or to look up replacements in a catalog
   * (possibly by using the public identifier).</p>
   *
   * @since SAX 1.0
   * @author David Megginson
   * @see org.xml.sax.XMLReader#setEntityResolver
   * @see org.xml.sax.InputSource
   */
  public interface EntityResolver {
  
  
      /**
       * Allow the application to resolve external entities.
       *
       * <p>The parser will call this method before opening any external
       * entity except the top-level document entity.  Such entities include
       * the external DTD subset and external parameter entities referenced
       * within the DTD (in either case, only if the parser reads external
       * parameter entities), and external general entities referenced
       * within the document element (if the parser reads external general
       * entities).  The application may request that the parser locate
       * the entity itself, that it use an alternative URI, or that it
       * use data provided by the application (as a character or byte
       * input stream).</p>
       *
       * <p>Application writers can use this method to redirect external
       * system identifiers to secure and/or local URIs, to look up
       * public identifiers in a catalogue, or to read an entity from a
       * database or other input source (including, for example, a dialog
       * box).  Neither XML nor SAX specifies a preferred policy for using
       * public or system IDs to resolve resources.  However, SAX specifies
       * how to interpret any InputSource returned by this method, and that
       * if none is returned, then the system ID will be dereferenced as
       * a URL.  </p>
       *
       * <p>If the system identifier is a URL, the SAX parser must
       * resolve it fully before reporting it to the application.</p>
       *
       * @param publicId The public identifier of the external entity
       *        being referenced, or null if none was supplied.
       * @param systemId The system identifier of the external entity
       *        being referenced.
       * @return An InputSource object describing the new input source,
       *         or null to request that the parser open a regular
       *         URI connection to the system identifier.
       * @exception org.xml.sax.SAXException Any SAX exception, possibly
       *            wrapping another exception.
       * @exception java.io.IOException A Java-specific IO exception,
       *            possibly the result of creating a new InputStream
       *            or Reader for the InputSource.
       * @see org.xml.sax.InputSource
       */
      public abstract InputSource resolveEntity (String publicId,
                                                 String systemId)
          throws SAXException, IOException;
  
  }
  
  // end of EntityResolver.java
  