ChartServlet.java Source code

Introduction

Here is the source code for ChartServlet.java

Source

import java.awt.*;
import java.awt.image.*;
import javax.imageio.*; // IF THIS FAILS TO COMPILE YOU NEED JDK1.4.
import javax.imageio.stream.*;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

/** Servlet to draw a Graphical Chart in response to a user request
 */
public class ChartServlet extends HttpServlet {
    private static int W = 300, H = 200;

    /** Draw a Graphical Chart in response to a user request */
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {

        response.setContentType("image/jpeg");

        // Create an Image
        BufferedImage img = new BufferedImage(W, H, BufferedImage.TYPE_INT_RGB);

        // Get the Image's Graphics, and draw.
        Graphics2D g = img.createGraphics();

        // In real life this would call some charting software...
        g.setColor(Color.white);
        g.fillRect(0, 0, W, H);
        g.setColor(Color.green);
        g.fillOval(100, 75, 50, 50);

        // Write the output
        OutputStream os = response.getOutputStream();
        ImageOutputStream ios = ImageIO.createImageOutputStream(os);

        if (!ImageIO.write(img, "jpeg", ios)) {
            log("Boo hoo, failed to write JPEG");
        }
        ios.close();
        os.close();
    }
}