programming-examples/java/Servlets_Session_Swing_Util/Simple download.java

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2019-11-15 12:59:38 +01:00
Simple download
package com.ack.web.servlet;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class SimpleDownload extends HttpServlet {
public void doGet( HttpServletRequest req, HttpServletResponse res )
throws ServletException, IOException {
res.setContentType( "application/msword" );
res.setHeader( "Content-Disposition",
"Attachment; Filename=testdoc.doc" );
ServletOutputStream os = res.getOutputStream();
// get resource as a url
URL resourceUrl = getServletContext().getResource( "/download/testdoc.doc" );
// open connection to resource
URLConnection con = null;
try {
con = resourceUrl.openConnection();
con.connect();
}
catch( IOException ioe ) {
res.sendError( HttpServletResponse.SC_INTERNAL_SERVER_ERROR,
"unable to read resource: /download/testdoc.doc" );
}
// set the actual content type in; must check that its non-null
String contentType = con.getContentType();
if( contentType != null ) {
res.setContentType( contentType );
}
// send resource contents back down output stream
try {
InputStream is = con.getInputStream();
byte[] buf = new byte[8096];
int bytesRead;
while( ( bytesRead = is.read( buf ) ) != -1 ) {
os.write( buf, 0, bytesRead );
}
}
catch( IOException ioe ) {
res.sendError( HttpServletResponse.SC_INTERNAL_SERVER_ERROR,
"unable to send resource to client: /download/testdoc.doc" );
}
}
}