testovals.java

来自「此源码为机械工业出版社出版的《Java语言程序设计》第三版所配套的书中所有源代码」· Java 代码 · 共 40 行

// TestOvals.java: Demonstrate drawing ovals
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.Color;
import java.awt.Graphics;

public class TestOvals extends JFrame
{
  // Default constructor
  public TestOvals()
  {
    setTitle("Show Ovals");
    getContentPane().add(new OvalsPanel());
  }

  // Main method
  public static void main(String[] args)
  {
    TestOvals frame = new TestOvals();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(250, 250);
    frame.setVisible(true);
  }
}

// The class for drawing the ovals on a panel
class OvalsPanel extends JPanel
{
  public void paintComponent(Graphics g)
  {
    super.paintComponents(g);

    g.drawOval(10, 30, 100, 60);
    g.drawOval(130, 30, 60, 60);
    g.setColor(Color.yellow);
    g.fillOval(10, 130, 100, 60);
    g.fillOval(130, 130, 60, 60);
  }
}