hotjavabrowserviewer.java

一个用java写的mail.里面的代码值得我们去研究！学习。

/*
** $Id: HotJavaBrowserViewer.java,v 1.3 2001/05/07 12:37:22 kunugi Exp $
**
** Copyright (c) 2000-2001 Jeff Gay
** on behalf of ICEMail.org <http://www.icemail.org>
** Copyright (c) 1998-2000 by Timothy Gerard Endres
** 
** This program is free software.
** 
** You may redistribute it and/or modify it under the terms of the GNU
** General Public License as published by the Free Software Foundation.
** Version 2 of the license should be included with this distribution in
** the file LICENSE, as well as License.html. If the license is not
** included with this distribution, you may find a copy at the FSF web
** site at 'www.gnu.org' or 'www.fsf.org', or you may write to the
** Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139 USA.
**
** THIS SOFTWARE IS PROVIDED AS-IS WITHOUT WARRANTY OF ANY KIND,
** NOT EVEN THE IMPLIED WARRANTY OF MERCHANTABILITY. THE AUTHOR
** OF THIS SOFTWARE, ASSUMES _NO_ RESPONSIBILITY FOR ANY
** CONSEQUENCE RESULTING FROM THE USE, MODIFICATION, OR
** REDISTRIBUTION OF THIS SOFTWARE. 
*/

package org.icemail.mail;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

import javax.activation.CommandObject;
import javax.activation.DataHandler;

import org.icemail.util.UserProperties;


/**
 * Class HotJavaBrowserViewer implements a CommandObject for the Java Activation Framework.
 * HotJavaBrowserViewer tries to display the contents of an HTML page using the
 * Hot Java library provided by Sun.
 * <p>
 * The only verb supported is "view", setting the contents of the HotJavaMailBrowser
 * and bringing into view.
 *
 * @see HotJavaMailBrowser
 */
public class HotJavaBrowserViewer
  implements CommandObject
{
  /**
   * Construct an empty viewer, which can be loaded later.
   */
  public
  HotJavaBrowserViewer() {
  }

  /**
   * Initialize the command object from the data handler as described by the verb.
   * <p>
   * Implements CommandObject.setCommandContext().
   * <p>
   * @param verb the command from the activation framework
   * @param dataHandler the datahandler containing the data contents and type
   * @see javax.activation.CommandObject
   */
  public void
  setCommandContext( String verb, DataHandler dataHandler ) throws IOException {
    if ( verb == null || dataHandler == null )
      throw new IOException( "Invalid parameters to HotJavaBrowserViewer.setCommandContext()" );
    if ( ! verb.equalsIgnoreCase( "view" ) )
      throw new IOException( "Only 'view' accepted to HotJavaBrowserViewer.setCommandContext()" );

    viewContent( dataHandler );
  }

    
  /**
   * sets the current message to be displayed in the viewer
   */
  private void
  viewContent( DataHandler dataHandler ) {
    String fileName = dataHandler.getName();
    if ( fileName == null ) {
      fileName = "unknown";
    }

    try {
      InputStream is = dataHandler.getInputStream();
      InputStreamReader source = new InputStreamReader( is );

      HotJavaMailBrowser.setBrowserDocumentSource( fileName, source );
    } catch ( IOException ex ) {
      ex.printStackTrace( System.err );
    }
  }

}