calledserviceservlet.java

Sun公司Dream项目

/*
 * The contents of this file are subject to the terms
 * of the Common Development and Distribution License
 * (the "License").  You may not use this file except
 * in compliance with the License.
 *
 * You can obtain a copy of the license at
 * http://www.opensource.org/licenses/cddl1.php
 * See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL
 * HEADER in each file and include the License file at
 * http://www.opensource.org/licenses/cddl1.php.  If 
 * applicable, add the following below this CDDL HEADER, 
 * with the fields enclosed by brackets "[]" replaced 
 * with your own identifying information: 
 * Portions Copyright [yyyy]
 * [name of copyright owner]
 */ 

/*
 * $(@)CalledServiceServlet.java $Revision: 1.1.1.1 $ $Date: 2006/03/15 13:12:10 $
 * 
 * Copyright 2006 Sun Microsystems, Inc. All Rights Reserved.
 */

package com.sun.sjc.idtv.vod.server.comm;

import java.io.*;
import java.net.*;
import javax.servlet.*;
import javax.servlet.http.*;

/**
  * This is the base class that all servlets that implements services
  * (i.e. those servlets that pass objects back and forth) should inherit
  * from.
  * 
  * @date October 2000
  */
  
abstract public class CalledServiceServlet extends HttpServlet
{
    public void doPost(HttpServletRequest request, HttpServletResponse response) 
	throws ServletException, IOException
    {
	doGet(request, response);
    }
	
    public void doGet(HttpServletRequest request, HttpServletResponse response) 
	throws ServletException, IOException
    {
	try
	    {
		// Read in the param
			
		int len = request.getContentLength();

		System.out.println("++++++++++++++++++++ LEN: " + len);			
		Serializable param = null;
			
		if (len != 0)
		    {
			InputStream in = new BufferedInputStream(request.getInputStream());
			
			byte[] data = new byte[len];

			int remain = len;
			while (remain > 0)
			    {
				int num = in.read(data, len-remain, remain);
					
				if (num < 0) throw new IOException();
					
				remain -= num;
			    }
				
			in.close();
			
			param = (Serializable) new ObjectInputStream(new ByteArrayInputStream(data)).readObject();
		    }
			

		// Call the business method		
		Serializable retObj = call(request, response, param);
			
		// Write out the return value
			
		// Be sure there's no caching anywhere
		response.setHeader("Pragma", "no-cache");
		response.setHeader("Cache-Control", "no-cache, no-store, must-revalidate, max-age=0");
		response.setIntHeader("Expires", 0);
			
		if (retObj != null)
		    {
			MyByteArrayOutputStream b_out;
			ObjectOutputStream o_out = new ObjectOutputStream(b_out = new MyByteArrayOutputStream());
				
			o_out.writeObject(retObj);
		
			response.setStatus(HttpServletResponse.SC_OK);
			response.setContentType("application/x-java-serialized-object");
			response.setContentLength(b_out.getCount());

			//System.out.println("++++++++++++++++++++ RETLEN: " + b_out.getCount());
						
			OutputStream out = response.getOutputStream();
			b_out.writeTo(out);
			out.flush();
			out.close();
		    }
		else
		    {			
			response.setStatus(HttpServletResponse.SC_OK);
			response.setContentType("application/x-java-serialized-object");
			response.setContentLength(0);
		    }
			
	    }
	catch (IOException e)
	    {
		System.out.println("CSS in exception: " + e);
			
		e.printStackTrace();
			
		throw e;
	    }
	catch (Exception e)
	    {
		e.printStackTrace();
		response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
		response.setContentType("application/x-java-serialized-object");
		response.setContentLength(0);
	    }
    }
  
    public abstract Serializable call(HttpServletRequest request, HttpServletResponse response, Serializable param)
	throws Exception;
  	
    // I created this class because I'm not sure that the size() method
    // will return the exact size of the data under all conditions. -- spt
    public static class MyByteArrayOutputStream extends ByteArrayOutputStream
    {
	public int getCount() { return count; }
    }
}