Patrick Awuah on educating leaders | Video on TED.com

2010-12-01T19:14:00.000+05:30

File Upload from Flex to Mysql Database:-Java Part

2010-03-17T00:46:00.001+05:30

Today I am going to describe how to insert the uploaded file in to Mysql database.For this we need apache fileupload jar files commons-fileupload-1.2.1.jar and commons.io-1.4.jar. . You can download the latest version of the package from http://commons.apache.org/downloads/download_fileupload.cgi.
Now first I am writing a class file

FileUploadListner.java

package servlet;

import org.apache.commons.fileupload.ProgressListener;

public class FileUploadListener implements ProgressListener
{
    private volatile long
      bytesRead = 0L,
      contentLength = 0L,
      item = 0L;

    public FileUploadListener()
    {
      super();
    }

    public void update(long aBytesRead, long aContentLength, int anItem)
    {
        bytesRead = aBytesRead;
        contentLength = aContentLength;
        item = anItem;
    }

    public long getBytesRead()
    {
        return bytesRead;
    }

    public long getContentLength()
    {
        return contentLength;
    }

    public long getItem()
    {
        return item;
    }
}

Now I am writing a servlet which will insert the file into database.

MyUploadServlet.java

package servlet;
import DBConnection;
import javax.servlet.http.HttpServlet;
import javax.servlet.Servlet;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Iterator;
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.FileItemFactory;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import java.sql.*;
public class MyUploadServlet extends HttpServlet implements Servlet
{
    private String filename;
    public MyUploadServlet()
    {
        super();
    }
protected void doGet(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException
    {
doPost(request,response);
    }
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException
    {
        DBConnection con=new DBConnection();
    PrintWriter ptr=response.getWriter();
    String jnan="";
// create file upload factory and upload servlet
        FileItemFactory factory = new DiskFileItemFactory();
        ServletFileUpload upload = new ServletFileUpload(factory);
        // set file upload progress listener
        FileUploadListener listener = new FileUploadListener();
        HttpSession session = request.getSession();
        session.setAttribute("LISTENER", listener);
        // upload servlet allows to set upload listener
        upload.setProgressListener(listener);
        List uploadedItems = null;
        FileItem fileItem = null;
         try
        {
            // iterate over all uploaded files
            uploadedItems = upload.parseRequest(request);
            Iterator i = uploadedItems.iterator();
            String str1[]={"","","","","","","","","","","","",""};
            int cc=0;
            while (i.hasNext())
            {
                fileItem = (FileItem) i.next();
                if(fileItem.isFormField() == true&&cc!=2)
                {
                jnan=String.valueOf(fileItem);
                jnan=jnan.substring(jnan.indexOf("FieldName=")+10,jnan.length());
                str1[cc]=jnan;
                cc++;
            }

        if (fileItem.isFormField() == false)
{
            if (fileItem.getSize() > 0)
            {
                File uploadedFile = null;
                String myFullFileName = fileItem.getName(),
                myFileName = "",
                slashType = (myFullFileName.lastIndexOf("\\") > 0) ? "\\" : "/"; // Windows or UNIX
                int startIndex = myFullFileName.lastIndexOf(slashType);
//Get File Name
myFileName = myFullFileName.substring(startIndex + 1, myFullFileName.length());
//Get File Extension
                String fileExt=myFileName.substring(myFileName.indexOf("."),myFileName.length());
// Create new File object

try{
ByteArrayInputStream bs=new ByteArrayInputStream(fileItem.get());
String query="INSERT INTO image(img) VALUES(?)";
PreparedStatement pst=con.conn.prepareStatement(query);
pst.setBinaryStream(1, bs,(int)fileItem.getSize());
pst.execute();
}
catch(Exception e)
{
System.out.println("in MyUploadServlet..Error:- "+e.getMessage());
}
}

                }

            }
        }
        catch (FileUploadException e)
        {
            System.out.println("in MyUploadServlet..Error:- "+e.getMessage());
        }
        catch (Exception e)
        {
            System.out.println("in MyUploadServlet..Error:- "+e.getMessage());
        }
        finally
        {
            con.DisconnectCon();
        }
    }
}

Here DBConnection is a class file.I am using this class to connect to mysql database from my eclipse.I made a connection pooling from apache tomcat 5.5 to Mysql.This class file is given below.
DBConnection.java:-

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.sql.DataSource;

public class DBConnection {

    private javax.naming.Context ic;
    private javax.sql.DataSource ds;
    public java.sql.Connection conn;

    public DBConnection()
    {
        try
        {

            ic=(Context)new InitialContext().lookup("java:comp/env");
            ds=(DataSource)ic.lookup("jdbc/MyJndiName");
            conn=ds.getConnection();
        }
        catch(Exception e)
        {
            System.out.println("Error in DBConnection "+e.getMessage());
        }
    }
    public void DisconnectCon()
    {
        try
        {
            conn.close();
        }
        catch(Exception e)
        {
            System.out.println("Error in DisconnectCon "+e.getMessage());
        }
    }
}

Done....The file is there in Database...
Thanks

Now We need to display the file from database into the flex RIA...I mean we have to Create an Image gallery in Flex!!! Comming Next

Image Upload from Flex RIA to MySql

2010-03-14T04:21:00.002+05:30

I am here going to describe how we can upload an image file from the Flex RIA to the database using java.I am using apache fileupload. You can download the latest version of the package from http://commons.apache.org/downloads/download_fileupload.cgi.
First we need to create a table in mysql.The table creation query is given below.

Now Open Flex builder 3.From File ->New->Flex Project.
Enter Project name as MyUplodProj.Click Finish button
It will open a new WindowedApplication

Now I am going to create a new file upload component.Right Click on the project name in Flex Navigator.Select New->MXML Component.Give component name as MyUploder.Click Finish.
The Code is:-

Now we need to insert this component in the application. So update as MyUplodProj.mxml as

Now we need to do the server side part.We have to create a servlet to handle this upload and to insert into database.It will come soon....

Just Started!!!

2010-03-12T12:22:00.001+05:30

Hai
I just started...I will add my experiences with file upload and download problems that I face while my project time.
So please Wait.....
The main Contents will be:

File upload to Mysql from jsp
File download from Mysql to jsp page
File upload from Flex RIA to Mysql
File download from Mysql to Flex RIA
All the above task to a folder in server.

COMMING SOON !!!!!

Have a nice Day

File Upload and Download

Patrick Awuah on educating leaders | Video on TED.com

File Upload from Flex to Mysql Database:-Java Part

Image Upload from Flex RIA to MySql

Just Started!!!