to upload a file to a remote server on the network

[sonia pandit]

how do make the server available for a file transfer over the network using code similar to this:
Got this code on the internet by the way the author is Muthu.
Right now I get an error message:

 
public void upload( String ftpServer, String user, String password,
         String fileName, File source ) throws MalformedURLException,
         IOException
   {
      if (ftpServer != null && fileName != null && source != null)
      {
         StringBuffer sb = new StringBuffer( "ftp://" );
         // check for authentication else assume its anonymous access.
         if (user != null && password != null)
         {
            sb.append( user );
            sb.append( ':' );
            sb.append( password );
            sb.append( '@' );
         }
         sb.append( ftpServer );
         sb.append( '/' );
         sb.append( fileName );
         /*
          * type ==> a=ASCII mode, i=image (binary) mode, d= file directory
          * listing
          */
         sb.append( ";type=i" );

         BufferedInputStream bis = null;
         BufferedOutputStream bos = null;
         try
         {
            URL url = new URL( sb.toString() );
            URLConnection urlc = url.openConnection();

            bos = new BufferedOutputStream( urlc.getOutputStream() );
            bis = new BufferedInputStream( new FileInputStream( source ) );

            int i;
            // read byte by byte until end of stream
            while ((i = bis.read()) != -1)
            {
               bos.write( i );
            }
         }
         finally
         {
            if (bis != null)
               try
               {
                  bis.close();
               }
               catch (IOException ioe)
               {
                  ioe.printStackTrace();
               }
            if (bos != null)
               try
               {
                  bos.close();
               }
               catch (IOException ioe)
               {
                  ioe.printStackTrace();
               }
         }
      }
      else
      {
         System.out.println( "Input not available." );
      }
   }


   

[Ulf Dittmer]

I'd advise to use a proper FTP client library like Apache Commons Net that takes care of all the details of the FTP protocol.

[sonia pandit]

Thanks, How do I prepare the server to be an Ftp server?

[Paul Clapham]

The code you posted looked like FTP client code to me. That would be code which uploads to an FTP server which is already running. Are you now saying you don't have a running FTP server yet?

If that's the case, then you get one and install it. That's a completely separate operation from writing code to upload data to it, and you can't use client code to create an FTP server or to start one. But perhaps I misunderstood that last question?

[sonia pandit]

Sorry I was not clear. I am not sure how to prepare a linux machine to be a ftp server. In other words I want to use the code I posted to access the ftp server. Does that make sense?

[John de Michele]

Sonia:

Try googling "linux ftp server setup". I was able to find some information that might be helpful.

John.

[Paul Clapham]

sonia pandit wrote:I am not sure how to prepare a linux machine to be a ftp server. In other words I want to use the code I posted to access the ftp server. Does that make sense?

No, it doesn't. At least, not the phrase "in other words" which implies the two statements somehow mean the same thing.

To prepare a machine to be an FTP server, you install some FTP server software on it and configure it appropriately. That only has to be done once. After that has been done -- and probably somebody in your organization has already done it -- then you can use code like what you posted to access it. This can be done as many times as necessary.

[sonia pandit]

I found a free perl script to use for uploading a file to the remote server at:

http://cgi.resourceindex.com/Programs_and_Scripts/Perl/File_Management/File_Uploading/

However, they do not seem to have a perl file to download a file from the remote server.

[Megha Singhal]

how can i upload file on remote server using http with java programming

[Swastik Dey]

http://commons.apache.org/proper/commons-fileupload/using.html

[Jeff Verdegan]

Megha Singhal wrote:how can i upload file on remote server using http with java programming

Try reading this thread, since that's what it's about.

[Megha Singhal]

alongwith following jsp i try to upload file using servlet

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>File Upload</title>
</head>
<body>
<form method="post" action="UploadServlet" enctype="multipart/form-data">
Select file to upload:
<input type="file" name="dataFile" id="fileChooser"/><br/><br/>
<input type="submit" value="Upload" />
</form>
</body>
</html>

save as upload.jsp

and then following servlet

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Iterator;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

public class UploadServlet extends javax.servlet.http.HttpServlet implements
javax.servlet.Servlet {
static final long serialVersionUID = 1L;
private static final String DATA_DIRECTORY = "resources";
private static final int MAX_MEMORY_SIZE = 1024 * 1024 * 2;
private static final int MAX_REQUEST_SIZE = 1024 * 1024;

public void doGet(HttpServletRequest req,HttpServletResponse res) throws ServletException, IOException
{
doPost(req, res);
}

protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out=response.getWriter();

boolean isMultipart = ServletFileUpload.isMultipartContent(request);
if (!isMultipart) {
return;
}


String filePath =null;
String fileName =null;
DiskFileItemFactory factory = new DiskFileItemFactory();
factory.setSizeThreshold(MAX_MEMORY_SIZE);
factory.setRepository(new File(System.getProperty("java.io.tmpdir")));
HttpSession session=request.getSession();
String uploadFolder = getServletContext().getRealPath("")+ File.separator + DATA_DIRECTORY;
ServletFileUpload upload = new ServletFileUpload(factory);
upload.setSizeMax(MAX_REQUEST_SIZE);
try {
List items = upload.parseRequest(request);
Iterator iter = items.iterator();
while (iter.hasNext()) {
FileItem item = (FileItem) iter.next();
if (!item.isFormField()) {
fileName = new File(item.getName()).getName();
filePath = uploadFolder + File.separator + fileName;
File uploadedFile = new File(filePath);
item.write(uploadedFile);
}
}

} catch (FileUploadException ex) {
throw new ServletException(ex);
}
catch (Exception ex) {
throw new ServletException(ex);
}
session.setAttribute("path",fileName);
request.getRequestDispatcher("/done.jsp").forward(request,response);

}
}

now i am getting following error

HTTP Status 500 -

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: Wrapper cannot find servlet class UploadServlet or a class it depends on
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
java.lang.Thread.run(Unknown Source)
root cause

java.lang.ClassNotFoundException: UploadServlet
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1360)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1206)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
java.lang.Thread.run(Unknown Source)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.16 logs.

Apache Tomcat/6.0.16

kindly help me.. i already set the path jar files like servlet api, commons io and java.

[Swastik Dey]

Megha,

Can you please show us the directory structure of your web application and the web.xml file.

[Megha Singhal]

Swastik Dey wrote:Megha,

Can you please show us the directory structure of your web application and the web.xml file.

yes sure..

first i made folder named it "upload" and within that folder i made another folder named "WEB-INF" and along with that folder i placed my jsp files their and within WEB-INF folder i made two folders named it "classes" in which i put my servlet file and another folder named "lib" that folder first i kept empty then i put commons.io jar files for uploading in that. also i already set path for the jar files in environmental variables.

[Swastik Dey]

Now show us the web.xml file please.

[Megha Singhal]

Swastik Dey wrote:Now show us the web.xml file please.

xml code

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>upload</display-name>
<welcome-file-list>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<description></description>
<display-name>UploadServlet</display-name>
<servlet-name>UploadServlet</servlet-name>
<servlet-class>UploadServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>UploadServlet</servlet-name>
<url-pattern>/UploadServlet</url-pattern>
</servlet-mapping>
</web-app>

[Swastik Dey]

Megha,

Put the servlet class inside a package, put the package inside WEB-INF\classes, and change the mapping in web.xml accordingly.

[Ivan Jozsef Balazs]

> put the package inside WEB-INF\classes

Or if the package is a jar file, then into WEB-INF/lib

[Megha Singhal]

Swastik Dey wrote:Megha,

Put the servlet class inside a package, put the package inside WEB-INF\classes, and change the mapping in web.xml accordingly.

you are talking about which package?.. i didn't understand.

[Swastik Dey]

You should have your own package that contains the .java file of servlet. For e.g.

package megha;
public class UploadServlet{
//your code goes here.
}

//you should read about java packages.
http://www.tutorialspoint.com/java/java_packages.htm

In simple language it's a sort of a folder where the .class file gets stored. So in your case there should be a folder called, megha that contains the .class file for UploadServlet. You should now copy this megha folder to
WEB-INF\classes, and change the mapping in web.xml

<servlet-mapping> 
<servlet-name>megha.UploadServlet</servlet-name> 
<url-pattern>/UploadServlet</url-pattern> 
</servlet-mapping> 

[Megha Singhal]

Swastik Dey wrote:You should have your own package that contains the .java file of servlet. For e.g.

package megha;
public class UploadServlet{
//your code goes here.
}

//you should read about java packages.
http://www.tutorialspoint.com/java/java_packages.htm

In simple language it's a sort of a folder where the .class file gets stored. So in your case there should be a folder called, megha that contains the .class file for UploadServlet. You should now copy this megha folder to
WEB-INF\classes, and change the mapping in web.xml

<servlet-mapping> 
<servlet-name>megha.UploadServlet</servlet-name> 
<url-pattern>/UploadServlet</url-pattern> 
</servlet-mapping> 

i understand what are packages but the i just wanted to know why we need to create packages.
it just a simple program that i want to run on tomcat.
package we usually make when we need to reuse it somewhere.
so can you please explain me why you you are suggesting me to use package here?

[Swastik Dey]

In the following post read the comments made by William Brogden

https://coderanch.com/t/545423/Tomcat/Unable-load-servlet-Tomcat