exceptionfilterchain.java

来自「RESIN 3.2 最新源码」· Java 代码 · 共 76 行

/*
 * Copyright (c) 1998-2008 Caucho Technology -- all rights reserved
 *
 * This file is part of Resin(R) Open Source
 *
 * Each copy or derived work must preserve the copyright notice and this
 * notice unmodified.
 *
 * Resin Open Source is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Resin Open Source 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, or any warranty
 * of NON-INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Resin Open Source; if not, write to the
 *   Free SoftwareFoundation, Inc.
 *   59 Temple Place, Suite 330
 *   Boston, MA 02111-1307  USA
 *
 * @author Scott Ferguson
 */

package com.caucho.server.dispatch;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import java.io.IOException;

/**
 * Represents the final servlet in a filter chain.
 */
public class ExceptionFilterChain implements FilterChain {
  // servlet
  private RuntimeException _runtimeException;
  private ServletException _servletException;

  /**
   * Create the exception filter chain.
   *
   * @param exception the exception to throw
   */
  public ExceptionFilterChain(Throwable exn)
  {
    if (exn instanceof RuntimeException)
      _runtimeException = (RuntimeException) exn;
    else if (exn instanceof ServletException)
      _servletException = (ServletException) exn;
    else
      _servletException = new ServletException(exn);
  }
  
  /**
   * Invokes the final servlet at the end of the chain.
   *
   * @param request the servlet request
   * @param response the servlet response
   */
  public void doFilter(ServletRequest request,
                       ServletResponse response)
    throws ServletException, IOException
  {
    if (_runtimeException != null)
      throw _runtimeException;
    else
      throw _servletException;
  }
}