code: package com.sun.xml.xsom.impl.parser.state;
  
  import org.xml.sax.Attributes;
  import org.xml.sax.SAXException;
  
  /**
   * 
   * 
   * @version $Id: NGCCHandler.java,v 1.9 2002/09/29 02:55:48 okajima Exp $
   * @author Kohsuke Kawaguchi (kk@kohsuke.org)
   */
  public abstract class NGCCHandler implements NGCCEventReceiver {
      protected NGCCHandler( NGCCEventSource source, NGCCHandler parent, int parentCookie ) {
              
          _parent = parent;
          _source = source;
          _cookie = parentCookie;
      }
      
      /**
       * Parent NGCCHandler, if any.
       * If this is the root handler, this field will be null.
       */
      protected final NGCCHandler _parent;
      
      /**
       * Event source.
       */
      protected final NGCCEventSource _source;
      
      /**
       * This method will be implemented by the generated code
       * and returns a reference to the current runtime.
       */
      protected abstract NGCCRuntime getRuntime();
      
      /**
       * Cookie assigned by the parent.
       * 
       * This value will be passed to the onChildCompleted handler
       * of the parent.
       */
      protected final int _cookie;
      
      // used to copy parameters to (enter|leave)(Element|Attribute) events.
      //protected String localName,uri,qname;
      
      
      /**
       * Notifies the completion of a child object.
       * 
       * @param result
       *      The parsing result of the child state.
       * @param cookie
       *      The cookie value passed to the child object
       *      when it is created.
       * @param needAttCheck
       *      This flag is true when the callee needs to call the
       *      processAttribute method to check attribute transitions.
       *      This flag is set to false when this method is triggered by
       *      attribute transition.
       */
      protected abstract void onChildCompleted( Object result, int cookie, boolean needAttCheck ) throws SAXException;
      
  //
  //
  // spawns a new child object from event handlers.
  //
  //
      public void spawnChildFromEnterElement( NGCCEventReceiver child,
          String uri, String localname, String qname, Attributes atts) throws SAXException {
          
          int id = _source.replace(this,child);
          _source.sendEnterElement(id,uri,localname,qname,atts);
      }
      public void spawnChildFromEnterAttribute( NGCCEventReceiver child,
          String uri, String localname, String qname) throws SAXException {
              
          int id = _source.replace(this,child);
          _source.sendEnterAttribute(id,uri,localname,qname);
      }
      public void spawnChildFromLeaveElement( NGCCEventReceiver child,
          String uri, String localname, String qname) throws SAXException {
              
          int id = _source.replace(this,child);
          _source.sendLeaveElement(id,uri,localname,qname);
      }
      public void spawnChildFromLeaveAttribute( NGCCEventReceiver child,
          String uri, String localname, String qname) throws SAXException {
              
          int id = _source.replace(this,child);
          _source.sendLeaveAttribute(id,uri,localname,qname);
      }
      public void spawnChildFromText( NGCCEventReceiver child,
          String value) throws SAXException {
              
          int id = _source.replace(this,child);
          _source.sendText(id,value);
      }
      
  //
  //
  // reverts to the parent object from the child handler
  //
  //
      public void revertToParentFromEnterElement( Object result, int cookie,
          String uri,String local,String qname, Attributes atts ) throws SAXException {
              
          int id = _source.replace(this,_parent);
          _parent.onChildCompleted(result,cookie,true);
          _source.sendEnterElement(id,uri,local,qname,atts);
      }
      public void revertToParentFromLeaveElement( Object result, int cookie,
          String uri,String local,String qname ) throws SAXException {
          
          if(uri==NGCCRuntime.IMPOSSIBLE && uri==local && uri==qname && _parent==null )
              // all the handlers are properly finalized.
              // quit now, because we don't have any more NGCCHandler.
              // see the endDocument handler for detail
              return;
          
          int id = _source.replace(this,_parent);
          _parent.onChildCompleted(result,cookie,true);
          _source.sendLeaveElement(id,uri,local,qname);
      }
      public void revertToParentFromEnterAttribute( Object result, int cookie,
          String uri,String local,String qname ) throws SAXException {
              
          int id = _source.replace(this,_parent);
          _parent.onChildCompleted(result,cookie,true);
          _source.sendEnterAttribute(id,uri,local,qname);
      }
      public void revertToParentFromLeaveAttribute( Object result, int cookie,
          String uri,String local,String qname ) throws SAXException {
              
          int id = _source.replace(this,_parent);
          _parent.onChildCompleted(result,cookie,true);
          _source.sendLeaveAttribute(id,uri,local,qname);
      }
      public void revertToParentFromText( Object result, int cookie,
          String text ) throws SAXException {
              
          int id = _source.replace(this,_parent);
          _parent.onChildCompleted(result,cookie,true);
          _source.sendText(id,text);
      }
  
  
  //
  //
  // error handler
  //
  //
      public void unexpectedEnterElement(String qname) throws SAXException {
          getRuntime().unexpectedX('<'+qname+'>');
      }
      public void unexpectedLeaveElement(String qname) throws SAXException {
          getRuntime().unexpectedX("</"+qname+'>');
      }
      public void unexpectedEnterAttribute(String qname) throws SAXException {
          getRuntime().unexpectedX('@'+qname);
      }
      public void unexpectedLeaveAttribute(String qname) throws SAXException {
          getRuntime().unexpectedX("/@"+qname);
      }
  }
  