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Create a JSP page with the name ImageDownload.jsp.

Add the following code to ImageDownload.jsp:

Code Block

title	ImageDownload.jsp
borderStyle	solid

<%@ 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>Download Image</title>
</head>
<body>
<h2>Name a Image to download</h2>
<form action="/WebJDBC/ImageDownload">
<table>
<tr>
<td>
Name of the Image
</td>
<td>
<Input type="text" name="ImageName">
</td>
</tr>
<tr>
<td>
<Input type="submit" value="submit">
</td>
<tr>
</table>
</form>
</body>
</html>

As can be seen from <form action="/WebJDBC/ImageDownload"> this JSP requests the ImageDownload servlet when the form is submitted.

Create a new servlet ImageDownload.java and add the following code:

Code Block

title	ImageDownload.java
borderStyle	solid

package jdbc;

import java.io.IOException;
import java.io.OutputStream;
import java.sql.Blob;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.annotation.Resource;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sql.DataSource;

 public class ImageDownload extends javax.servlet.http.HttpServlet implements javax.servlet.Servlet {
	 @Resource(name = "jdbc/userds")
		private DataSource ds;
   static final long serialVersionUID = 1L;
   
	public ImageDownload() {
		super();
	}   	
	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doProcess(request, response);	
	}  	
	protected void doProcess(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		Connection dbconnect = null;
		ResultSet rs = null;
		PreparedStatement stmnt = null;
		try {
			dbconnect = ds.getConnection();
			String s=request.getParameter("ImageName");
			stmnt = dbconnect.prepareStatement("SELECT PIC FROM PICTURES WHERE NAME=?");
			stmnt.setString(1, s);
			rs = stmnt.executeQuery();
			if (rs.next()) {
				// Get as a BLOB
				Blob aBlob = rs.getBlob(1);
				byte[] b = new byte[4096];
				java.io.InputStream ip = aBlob.getBinaryStream();
				OutputStream out = null;
				int c = 0;
				out = response.getOutputStream();
				response.setContentType("image/jpeg");
				while (c != -1) {
					                                     c = ip.read(b);
					                                     if (c > 0) {
                                       out.write(b);
					, 0, c);
                                       out.flush();
				         }
				ip.close();
				
			}

		} catch (Exception e) {
			e.printStackTrace();
		} finally {
        	try{
        		dbconnect.close();
        		stmnt.close();
        	    rs.close();
        	}catch(SQLException e){
        		e.printStackTrace();
        	}        	        	
        }

	} 
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doProcess(request, response);
	}   	  	    
}

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