oval.java~3~

很好得jbuilder100例源代码

package updot;

import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class oval extends Applet {
  boolean isStandalone = false;
  int i;
  int a[]={0,0,255};
  boolean flag[]={true,true,false};
  Color mycolor;
  int x,y;
  /**Get a parameter value*/
  public String getParameter(String key, String def) {
    return isStandalone ? System.getProperty(key, def) :
      (getParameter(key) != null ? getParameter(key) : def);
  }

  /**Construct the applet*/
  public oval() {
  }
  /**Initialize the applet*/
  public void init() {
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }
  /**Component initialization*/
  private void jbInit() throws Exception {
    this.setBackground(Color.white);
    this.addMouseListener(new java.awt.event.MouseAdapter() {
      public void mousePressed(MouseEvent e) {
        this_mousePressed(e);
      }
    });
  }
  /**Get Applet information*/
  public String getAppletInfo() {
    return "Applet Information";
  }
  /**Get parameter info*/
  public String[][] getParameterInfo() {
    return null;
  }
 public void update(Graphics g){
 paint(g);
 x=x-10;
 y=y-10;
 }
  void this_mousePressed(MouseEvent e) {
    x=e.getX();
    y=e.getY();
    for(i=0;i<3;i++){
      if(a[i]<=10)
          flag[i]=true;
      if(a[i]>=245)
          flag[i]=false;
      if(flag[i]==true)
         a[i]+=10;
      else
         a[i]-=10;
     }
    repaint();
  }
  public void paint(Graphics g){
   mycolor=new Color(a[0],a[1],a[2]);
   g.setColor(mycolor);
   g.fillOval(x-10,y-10,20,20);
  }
}