displaying image in jsp from sql using helper servlet

[ekansh singh]

I am struck on a simple problem
I have to display an image from a database. I have successfully uploaded the image in database.
now for displaying image on JSP I have a servlet which is doing this work

This servlet is stored in src folder under package action. Actually I am using struts2 and i dont know how to display it using struts2.
So my servlet is like this

public class ImageHelperServlet extends HttpServlet {

	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		super.doGet(request, response);
		Integer imageId = Integer.parseInt( (String) request.getParameter("imageId"));  
		ImagesUDDaoInterface imagesUDDaoInterface;
		try {
				imagesUDDaoInterface = new ImagesUDDao();
				byte[] picBytes=imagesUDDaoInterface.getImage(imageId);
				response.setContentType("image/jpeg"); 
				response.getOutputStream().write(picBytes);  
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		

getImage functionality is like this

public byte[] getImage(Integer imageId) {
		Connection conn = null;
		 PreparedStatement  pstmt = null;
		 byte[] picBytes = new byte[20000];
	ResultSet rs;
		try {
			conn =  dbConnector.getConnection();
			pstmt = conn.prepareStatement("SELECT * FROM filepool WHERE id =?");
			pstmt.setInt(1, imageId);
			rs = pstmt.executeQuery();
			if (rs.next()) {  
					Blob pic = (Blob) rs.getBlob("filename");  
				picBytes = pic.getBytes(1, (int) pic.length());  
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (Exception e) {
			System.out.println("exception genrated "+e);
		}
				return picBytes;
	}

}
[/code]

On JSP my code is

<IMG src="<%=getServletContext().getContextPath()%>/ImageHelperServlet?imageId=1" height="100" width="100"/>

on searching on net i found this also

<IMG src="<%=getServletContext().getContextPath()%>/servlet/ImageHelperServlet?imageId=1" height="100" width="100"/>

i tried using both but I am unable to display the image

[Bear Bibeault]

When hitting the servlet directly in the browser displays the image, it will work from an <img> tag in an HTML page.

So work on your servlet -- make sure that it returns the right data and has the correct response headers set.

[Bear Bibeault]

        super.doGet(request, response);      

Why are you doing this?

[Bauke Scholtz]

ekansh singh wrote:Actually I am using struts2 and i dont know how to display it using struts2.

This is irrelevant. Struts is just another MVC framework.

i tried using both but I am unable to display the image

Aside from a lot of logic faults and resource leaks I see two huge flaws: 1) you're calling super.doGet() in the servlet and 2) you're getting only the first 20000 bytes of an image and ignoring the rest in the DAO.

Check the 2nd example of this article how to do it properly: http://balusc.blogspot.com/2007/04/imageservlet.html
As a suggestion, first test the image independently in your webbrowser without using HTML <img> element.