Memory Leak for Graphics2D.drawString?

Question

Hi, all!!
I am a Java Programmer who is experienced in Swing application on a windows platform.
I have developed a code snipplet to print out to use Graphics2D.drawString method.
Then, I have encountered the performance degrade that the number of objects are created per call for the method.
It seems that there is a difference among JDKs.
When such a method is called, the number of objects are created is the followings
Java1.4 | 138
Java5 | 946
Java6 | 1217
Is this a known bug that JDK has since JDK has changed graphically from Tiger?
or is it related to memory leak?
Thank you in advance
Edited by: Yuichi_Yamada on Jun 30, 2008 5:31 AM

Answer 1

Yuichi_Yamada wrote:
Is there a noticeable performance degradation in your application (from the user's perspective?)Compared to Java1.4, it takes 4 times longer to finish print-outs for large volume of data.Please post the example you're benchmarking. I wrote up a quick little micro-benchmark (I know I know, not a 100% accurate benchmark, but just as a quick test), and could not reproduce the performance degradation time-wise (I didn't test memory usage). In fact, with this benchmark, it appears that 1.6 is around 3x faster with Graphics#drawString() than 1.4:
Printing "Hello, world!" 500,000 times (approximate average of 10 runs):
1.4 - 5600ms
1.5 - 2300ms
1.6 - 1920ms
Printing "Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!" 500,000 times) (approximate average of 10 runs):
1.4 - 30833ms
1.6 - 8844ms
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import javax.swing.*;
public class DrawStringMicroBenchmark extends JFrame {
     private BufferedImage bi;
     private JTextField toPaintField;
     private SpinnerNumberModel iterModel;
     private JTextArea resultArea;
     public DrawStringMicroBenchmark() {
          bi = new BufferedImage(300,300, BufferedImage.TYPE_INT_RGB);
          JPanel cp = new JPanel(new BorderLayout());
          JPanel dataPanel = createDataPanel();
          cp.add(dataPanel, BorderLayout.NORTH);
          JPanel buttonPanel = new JPanel();
          JButton b = new JButton("Repaint");
          b.addActionListener(new ActionListener() {
               public void actionPerformed(ActionEvent e) {
                    runTest();
          buttonPanel.add(b);
          cp.add(buttonPanel, BorderLayout.SOUTH);
          setContentPane(cp);
          setTitle("Graphics2D#drawString() Micro Benchmark");
          setDefaultCloseOperation(EXIT_ON_CLOSE);
          pack();
     private JPanel createDataPanel() {
          JPanel dataPanel = new JPanel();
          dataPanel.setLayout(new BoxLayout(dataPanel, BoxLayout.Y_AXIS));
          dataPanel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
          toPaintField = new JTextField("Hello world!", 30);
          dataPanel.add(createLabeledItem("String to paint: ", toPaintField));
          JSpinner iterSpinner = createIterSpinner();
          iterModel = (SpinnerNumberModel)iterSpinner.getModel();
          dataPanel.add(createLabeledItem("Iterations: ", iterSpinner));
          resultArea = new JTextArea(5, 30);
          resultArea.setEnabled(false);
          resultArea.setEditable(false);
          dataPanel.add(createLabeledItem("Result: ", new JScrollPane(resultArea)));
          dataPanel.add(Box.createVerticalGlue());
          return dataPanel;
     private JPanel createLabeledItem(String label, JComponent item) {
          JPanel temp = new JPanel(new BorderLayout());
          temp.add(new JLabel(label), BorderLayout.LINE_START);
          temp.add(item);
          return temp;
     private JSpinner createIterSpinner() {
          SpinnerModel model = new SpinnerNumberModel(50000, 1,Integer.MAX_VALUE, 1000);
          return new JSpinner(model);
     private void runTest() {
          String text = toPaintField.getText();
          int iter = ((Integer)iterModel.getValue()).intValue();
          Graphics2D g2d = bi.createGraphics();
          long start = System.currentTimeMillis();
          for (int i=0; i<iter; i++) {
               g2d.drawString(text, 30, 30);
          long time = System.currentTimeMillis() - start;
          resultArea.append(iter+ " iterations: " + time + " ms\n");
     public static void main(String[] args) {
          SwingUtilities.invokeLater(new Runnable() {
               public void run() {
                    new DrawStringMicroBenchmark().setVisible(true);
}