org.figure8.join.control
Class DownloadServlet

java.lang.Object
  javax.servlet.GenericServlet
      javax.servlet.http.HttpServlet
          org.figure8.join.control.DownloadServlet

All Implemented Interfaces:

java.io.Serializable, javax.servlet.Servlet, javax.servlet.ServletConfig

public class DownloadServlet
extends javax.servlet.http.HttpServlet

Servlet that allows to download a file which full UNC path is put into to the query parameters ("path" denotes the directory and "file" short name of file itself).

Version:

$Revision: 1.2 $

Author:

Laurent Broudoux

See Also:

Serialized Form

Field Summary

protected java.lang.String	notExistsURL URL to redirect to in case the specified file does not exists.
protected java.lang.String	notReadableURL URL to redirect to in case the specified file is not readable.

Constructor Summary

DownloadServlet()

Method Summary

void	doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) Override of default doGet() method: just call the protected downloadFile() method, passing around request and response.
protected void	downloadFile(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) Retrieve the file to download path from query string.
protected void	dumpFile(java.io.File file, java.io.OutputStream os) Dump a file content into the given ouput stream.
void	init() Override of default init() method.

Methods inherited from class javax.servlet.http.HttpServlet

doDelete, doHead, doOptions, doPost, doPut, doTrace, getLastModified, service, service

Methods inherited from class javax.servlet.GenericServlet

destroy, getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, log, log

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

notExistsURL

protected java.lang.String notExistsURL

URL to redirect to in case the specified file does not exists.

notReadableURL

protected java.lang.String notReadableURL

URL to redirect to in case the specified file is not readable.

Constructor Detail

DownloadServlet

public DownloadServlet()

Method Detail

init

public void init()
          throws javax.servlet.ServletException

Override of default init() method. Call super.init() and then retrieve and store servlet parameters.

Overrides:

init in class javax.servlet.GenericServlet

Throws:

javax.servlet.ServletException - if one init parameter is missing

doGet

public void doGet(javax.servlet.http.HttpServletRequest request,
                  javax.servlet.http.HttpServletResponse response)
           throws javax.servlet.ServletException,
                  java.io.IOException

Override of default doGet() method: just call the protected downloadFile() method, passing around request and response.

Overrides:

doGet in class javax.servlet.http.HttpServlet

Parameters:

request - The http request (containing query string specifying file)

response - Thee http response (for writing ouput)

Throws:

java.io.IOException - if requested file cannot be opened or written to response

javax.servlet.ServletException - in any other exception case

downloadFile

protected void downloadFile(javax.servlet.http.HttpServletRequest request,
                            javax.servlet.http.HttpServletResponse response)
                     throws java.io.IOException

Retrieve the file to download path from query string. Make some check (non null, existence, readability) before dumping the file into ouputstream. If gzip encoding is supported, wrap the dump into a GZIPOutputStream to save bandwidth ...

Parameters:

request - The http request (containing parameters specifying file)

response - Thee http response (for writing ouput)

Throws:

java.io.IOException - if outputstream cannot be opened or written

dumpFile

protected void dumpFile(java.io.File file,
                        java.io.OutputStream os)

Dump a file content into the given ouput stream. Best efforts are made to cleanly flush & close input and ouput streams.

Parameters:

file - The file to dump

os - The ouput stream to dump in