Image Upload

index.jsp

<form name="form" onSubmit='return validate();' action="change_photo.do" method="post" enctype="multipart/form-data">
                        <span style="padding-left: 30px">Upload Picture : <input type ="file"  id="fileChooser"  name="pic" style="margin-left: 23px"/></span><br /><br/>
                        <span class="submit" ><input type="submit" value="Change Photo" name="submit"/></span>
                    </form>

validation


<script type="text/javascript">
            function validate()
{
var extensions = new Array("jpg","png");
var pic = document.form.pic.value;
var image_length = document.form.pic.value.length;
var pos = pic.lastIndexOf('.') + 1;
var ext = pic.substring(pos, image_length);
var final_ext = ext.toLowerCase();


for (i = 0; i < extensions.length; i++)
{
        if(extensions[i] == final_ext)
        {
           
        if(val()){
        return true;
        }
        }
}
alert("You must upload file with one of the following extensions: "+ extensions.join(', ') +".");
return false;
}

        </script>



change_photo.java



package com;
import java.io.File;
import java.io.IOException;
import java.sql.*;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Random;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import model.DbConnection;

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

/**
 * Servlet implementation class UploadServlet
 * @version 1.0
 * @author www.codejava.net
 */
public class change_photo extends HttpServlet {
    private static final long serialVersionUID = 1L;
    private static final String UPLOAD_DIRECTORY = "upload";
    private static final int THRESHOLD_SIZE = 1024 * 1024 * 3; // 3MB
    private static final int MAX_FILE_SIZE = 1024 * 1024; // 4MB
    private static final int REQUEST_SIZE = 1024 * 1024 * 1; // 5MB

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
     *      response)
     */
    protected void doPost(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        try {
            DbConnection dbc=new DbConnection();
            Connection con=dbc.getCon();
            Statement st=null;
            ResultSet rs=null;
            PreparedStatement pst=null;
            String finalImg="";
            String value="";
            String value1="";
            HttpSession hs=request.getSession();
            String id=(String)hs.getAttribute("id");
            st=con.createStatement();         
            // checks if the request actually contains upload file
            if (!ServletFileUpload.isMultipartContent(request)) {
                // if not, we stop here
                return;
            }
            
            // configures some settings
            DiskFileItemFactory factory = new DiskFileItemFactory();
            factory.setSizeThreshold(THRESHOLD_SIZE);
            factory.setRepository(new File(System.getProperty("java.io.tmpdir")));
            
            ServletFileUpload upload = new ServletFileUpload(factory);
            upload.setFileSizeMax(MAX_FILE_SIZE);
            upload.setSizeMax(REQUEST_SIZE);
            
            // constructs the directory path to store upload file
            String uploadPath = getServletContext().getRealPath("")
                + File.separator + UPLOAD_DIRECTORY;
            // creates the directory if it does not exist
            File uploadDir = new File(uploadPath);
            if (!uploadDir.exists()) {
                uploadDir.mkdir();
            }
             System.out.print("file is there");
            ArrayList<String> ll=new ArrayList<String>();
            try
            {
                // parses the request's content to extract file data
                List formItems = upload.parseRequest(request);
                int s=formItems.size();
                for(int i=0;i<1;i++)
                {
                                Iterator iter = formItems.iterator();

                                // iterates over form's fields

                                while (iter.hasNext())
                                {
                                    FileItem item = (FileItem) iter.next();
                                    // processes only fields that are not form fields
                                    if (!item.isFormField())
                                    {
                                        String fileName = item.getName();
                                        Random gen = new Random();
                                            int r = Math.abs(gen.nextInt());

                                            String reg = "[.*]";
                                            String replaceText = "";
                                            String finalname=fileName;
                                           
                                            System.out.print(finalname);
                                            //System.out.println("Text before replacing is: " + fileName);
                                            Pattern pattern = Pattern.compile(reg);
                                            Matcher matcher = pattern.matcher(fileName);

                                            StringBuffer buffer = new StringBuffer();
                                            while(matcher.find())
                                            {
                                                matcher.appendReplacement(buffer, replaceText);
                                            }
                                            int indexOf = fileName.indexOf(".");
                                            String domainName = fileName.substring(indexOf);
                                            //System.out.println("Domain Name: "+ domainName);
                                            //System.out.print(buffer.toString());
                                            finalImg = buffer.toString()+r+i+domainName;
                                            ll.add(finalImg);

                                            System.out.println("Final Image: "+ finalImg);




                                        String filePath = uploadPath +  File.separator + finalImg;
                                        File storeFile = new File(filePath);
                                        //System.out.print(filePath);
                                        // saves the file on disk
                                        item.write(storeFile);
                                      
                                   
                                }
                  
                                   
                                   

                   
                   
                                 
                }
            }
              
                    String sql="UPDATE `tbl_employee` SET `pic`=? WHERE id=?";
                    pst=con.prepareStatement(sql);
               
                    Iterator<String> iter=ll.iterator();
                   
                    for(int i=1;iter.hasNext();i++)
                    {
                        String name=iter.next();
                        pst.setString(i,name);
                    }
                    pst.setString(2, id);
                   
                   
                   
                    int i=pst.executeUpdate();
               
                System.out.print("inserted" +i);
                request.setAttribute("message", "Upload has been done successfully!");
            }
            catch (SQLException ex) {
                 request.setAttribute("message", "Something Went Wrong.");
            }
           
        } catch (Exception ex) {
            request.setAttribute("message", "There was an error: Size Of photo must be less than (1 MB)");
        }
        getServletContext().getRequestDispatcher("/ChangePic.jsp").forward(request, response);
    }
}