frame1.java

jbuilder2005

package cubiccurvetest;

import java.awt.*;
import javax.swing.*;
import java.awt.geom.*;

public class Frame1
    extends JFrame {
  JPanel contentPane;
  BorderLayout borderLayout1 = new BorderLayout();

  public Frame1() {
    try {
      setDefaultCloseOperation(EXIT_ON_CLOSE);
      jbInit();
    }
    catch (Exception exception) {
      exception.printStackTrace();
    }
  }

  /**
   * Component initialization.
   *
   * @throws java.lang.Exception
   */
  private void jbInit() throws Exception {
    contentPane = (JPanel) getContentPane();
    contentPane.setLayout(borderLayout1);
    setSize(new Dimension(300, 200));
    setTitle("绘制三次曲线");
  }
  public void paint(Graphics g)  {
    Graphics2D g2d = (Graphics2D) g;
    CubicCurve2D c1 = new CubicCurve2D.Double(10, 100, 80, 180, 220, 20, 290,100);
    CubicCurve2D c2 = new CubicCurve2D.Double(10, 100, 80, 20, 220, 180, 290,100);
            //两条曲线的端点相同，都是(10,100)和(290,100)
    g2d.setColor(Color.red); //或是 g.setColor(Color.red);
    g2d.draw(c1);            //用红色画第一条曲线
    g2d.setColor(Color.blue);
    g2d.draw(c2);            //第二条，蓝色
}

}