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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);
					out.write(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);
	}   	  	    
}

...

Code Block

title	geronimo-web.xml
borderStyle	solid

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://geronimo.apache.org/xml/ns/j2ee/web-2.0.1"
         xmlns:nam="http://geronimo.apache.org/xml/ns/naming-1.2"
         xmlns:sec="http://geronimo.apache.org/xml/ns/security-2.0" 
         xmlns:sys="http://geronimo.apache.org/xml/ns/deployment-1.2">
  <sys:environment>
    <sys:moduleId>
      <sys:groupId>default</sys:groupId>
      <sys:artifactId>WebJDBC</sys:artifactId>
      <sys:version>1.0</sys:version>
      <sys:type>car</sys:type>
    </sys:moduleId>
   <sys:dependencies>
            <sys:dependency>
                <sys:groupId>console.dbpool</sys:groupId>
                <sys:artifactId>userds<artifactId>jdbc_userds</sys:artifactId>
            </sys:dependency>
    </sys:dependencies>
  </sys:environment>
  <context-root>/WebJDBC</context-root>
  <nam:resource-ref>
        <nam:ref-name>jdbc/userds</nam:ref-name>
        <nam:pattern>
          <nam:groupId>console.dbpool</nam:groupId>
          <nam:artifactId>userds<artifactId>jdbc_userds</nam:artifactId>
          <nam:name>jdbc/userds</nam:name>
        </nam:pattern>
    </nam:resource-ref>
</web-app>

<sys:dependency>- The dependency element is to suggest the dependency of the application on the database pool. In our case we have userds as a dependency module.
<nam:resource-ref>- This element is used to map the JDBC connenction pool with a user defined name. In our case we have mapped jdbc/userds with jdbc_userds.

Deploy and run

Start the server within Eclipse.
Right click on WebJDBC project and select Run as - > Run on server.
Once done the application will be deployed on the server.
Launch the application with the following link http://localhost:8080/WebJDBC/
Fill up the form with the a image location and name. The same name will be used while populating the database with the image data. Select Submit once done.
If your image is successfully inserted into the database you will get a Congratulation message.
To retrieve an image from the database launch the following portlet http://localhost:8080/WebJDBC/ImageDownload.jsp. Select submit once done.
This will display the image in the browser.

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Deploy and run