Ajax代理的Java Servlet的实现

import javaioIOException;

import javaioInputStream;

import URL;

import javaxservletServletConfig;

import javaxservletServletException;

import javaxservletServletOutputStream;

import javaxservlethttpHttpServlet;

import javaxservlethttpHttpServletRequest;

import javaxservlethttpHttpServletResponse;

/**

* Take any request and proxy it to the given REDIRECT_BASE

* For example if this servlet lives at

*

*

*

* and is inititialized with the REDIRECT_BASE

*

*

*

* then a GET request like

*

*

*

* will return the results of a GET from

*

*

*

* This is not robust and generalized; its simple and quick

*

* @author jdf

*

*/

public class ProxyServlet extends HttpServlet

{

private final static String COPYRIGHT = comibmdogearCopyrightSHORT;

public static final String REDIRECT_BASE = comibmblservletRedirectServletredirect_base;

private String redirectBase;

@Override

public void init（ServletConfig config） throws ServletException

{

superinit（config）

redirectBase = getRequiredParam（REDIRECT_BASE）

}

@Override

protected void doGet（HttpServletRequest req HttpServletResponse resp） throws IOException

{

String queryString = reqgetQueryString（）

URL url = new URL（redirectBase + （queryString != null ? ? + queryString : ））

copyInputStreamToOutputStream（urlopenStream（） respgetOutputStream（））

}

private void copyInputStreamToOutputStream（InputStream in ServletOutputStream out）

throws IOException

{

try

{

try

{

byte[] buffer = new byte[];

int n;

while （（n = inread（buffer）） != ）

outwrite（buffer n）

}

finally

{

outclose（）

}

}

finally

{

inclose（）

}

}

protected String getRequiredParam（String param） throws ServletException

{

String result = getServletConfig（）getInitParameter（param）

if （result == null） {

throw new ServletException（getClass（） + requires + param + param）

}

return result;

}

}