Displaying images stored in the database

[Mary White]

Hi,
I'm saving image files (bmp, jpg, gif) in the database as binary data (I'm using SQL Server). Then, I have to retrieve this file and show the image in a JSP.
I'm using Struts 1.1, SQLServer and weblogic.
How can I do this?
Thanks

[alzamabar]

I would suggest first to get a connection to the database and in someway to get a Collection of 'binary data images'; then, applying the same pattern used to convert images from their format to binary format, but on the way back, use the <html:image> Struts tag to display it on your page.
My 2 cents.

[Dave Hewitson]

I was looking for a good solution to the same problem a couple of months back.
This solution may not be the best, but It was the only one I could find at the time - performance was ok using MySQL but awful on DB2 - you'll have to see for yourself.
Anyway, I used a helper servlet to get the binary data from the DB - here's the code...

public class ImageHelperServlet extends HttpServlet {
/**Process the HTTP Get request*/
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String url = "jdbc:mysql://localhost/personnel";
String employeeNum = (String) request.getParameter("employeeNum");
//System.out.println("Getting image for employee number " + employeeNum);
String sql = "SELECT Picture FROM person WHERE EmployeeNum =" + employeeNum;
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
try {
Class.forName("org.gjt.mm.mysql.Driver");
// SQL Request
con = DriverManager.getConnection(url, "hewitsd", "password");
stmt = con.createStatement();
rs = stmt.executeQuery(sql);
if (rs.next()) {
com.mysql.jdbc.jdbc2.Blob pic = (com.mysql.jdbc.jdbc2.Blob) rs.getBlob("Picture");
byte[] picBytes = pic.getBytes(1, (int) pic.length());
response.setContentType("image/jpeg");
response.getOutputStream().write(picBytes);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
rs.close();
} catch (Exception e) {}
try {
stmt.close();
} catch (Exception e) {}
try {
con.close();
} catch (Exception e) {}
}
}
}

The in my jsp I have...

<IMG src="<%=contextPath%>/servlet/mysql.ImageHelperServlet?employeeNum=123456" height="100" width="100"/>  

Hope this helps.
Regards
Dave.

[Mary White]

Thanks Dave, your suggestion was really good

[Graham Mead]

Hi Mary
Not used it myself but you could have a butchers at the JDBC 2.0 Blob interface
Found these links
http://java.sun.com/j2se/1.4/docs/guide/jdbc/blob.html
http://developer.java.sun.com/developer/onlineTraining/Database/JDBC20Intro/exercises/BLOBGet/index.html
The interface seems to reduce the amount of code you need to write but it might be an alternative.