一个JAVA画图程序

               近期根据视频教程搞了一个JAVA画图程序，做了一个太阳系模型的源码。涉及到一些AWT和面向对象的东西。详细来看一下吧。

先来看一下效果吧:

基本的画图理论就省略了。要实现该程序关键有二个通用的程序：

一、继承Frame的一个窗口初始化程序

public class  MyFrame extends Frame {
public void LaunchFrame() {
setSize(Constants.FRAME_WIDTH,Constants.FRAME_HIGH);
setLocation(100,100);
setVisible(true);
setBackground(Color.BLACK);
addWindowListener(new WindowAdapter() {
@Override
public void windowClosing(WindowEvent arg0) {
System.exit(0);
}

});
new RepaintThread().start();
}
class RepaintThread extends Thread {                //启动一个线程反复画图，是实现主程序中的Paint（）方法，实现动画效果，很关键！！！！！
public void start() {
while (true) {
repaint();
try {
sleep(40);
} catch (InterruptedException e) {
e.printStackTrace();
}

}

}
}
}

二、 获取图片资源（在后面的程序中反复用到）

public static Image getImage(String path) {

URL u=GameUtil.class.getClassLoader().getResource(path);
BufferedImage img=null;
try {
img=ImageIO.read(u);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return img;
}
}

     主程序中使用继承和重载构建了两个类START和PLANET：

一首先Start类，主要功能是画星体。

public class Stars {
   Image img;
   double x,y;
   int width,high;
   
   public void draw(Graphics g) {
  g.drawImage(img,(int)x,(int)y,null);

}
   public Stars()
   {
  
   }
   public Stars(String path,double x,double y) {
  this.img=GameUtil.getImage(path);
  this.width=img.getWidth(null);
  this.high=img.getHeight(null);
  this.x=x-width/2;
  this.y=y-high/2;
  

}
   public Stars(Image img){
  this.img=img;
  this.width=img.getWidth(null);
  this.high=img.getHeight(null);


   }
   
}

二、Planet类继承与Start类，主要实现星体的运行轨迹计算和围绕实现。

public class Planet extends Stars{


/**
 * 星体的属性
 *  */
double longAxis;//长轴
double shortAxis;//短轴 
double speed;//速度
double degree;//角度
Stars center;//用于计算星体的中心位置。
boolean issatelite;

public void draw(Graphics g) {
/*
* 画椭圆轨迹
* */
  g.drawImage(img, (int)x,(int)y,null);
  if(!issatelite){
  drawTrace(g);
  }
    move();
 
}
public void move(){
  x=(center.x+center.width/2-img.getWidth(null)/2)+longAxis*Math.cos(degree);
  y=(center.y+center.high/2-img.getHeight(null)/2)+shortAxis*Math.sin(degree);
  
  degree+=speed;
}
public void  drawTrace(Graphics g) {
double ovalx,ovaly,ovalwidth,ovalheight;
ovalx=(center.x+center.width/2)-longAxis;
ovaly=(center.y+center.high/2)-shortAxis;
ovalwidth=longAxis*2;
ovalheight=shortAxis*2;


//避免画笔改动
Color c=g.getColor();
g.setColor(Color.RED);
g.drawOval((int)ovalx,(int)ovaly,(int)ovalwidth,(int)ovalheight);
g.setColor(c);

}




public Planet( Stars center,String path, double longAxis,
double shortAxis, double speed) {
super(GameUtil.getImage(path));
this.center = center;
this.x=center.x+longAxis;
this.y=center.y;
//this.img=GameUtil.getImage(path);
this.longAxis = longAxis;
this.shortAxis = shortAxis;
this.speed = speed;

}
public Planet( Stars center,String path, double longAxis,
double shortAxis, double speed,boolean issatelite) {
this(center,path,longAxis,shortAxis,speed);
this.issatelite=issatelite;

}
public Planet(String path, double x, double y) {
super(path, x, y);

}


}

另外在主程序中调用就可以了：

public class MySolarFrame  extends MyFrame{


//Image img=GameUtil.getImage("images/sun.png");
Stars sun=new Stars("images/sun.png", Constants.FRAME_WIDTH/2, Constants.FRAME_HIGH/2);
Planet earth=new Planet(sun,"images/earth.png", 220, 180,0.01);
Planet mars=new Planet(sun,"images/3.png", 300, 250,0.02);
Planet venus=new Planet(sun,"images/Venus.png", 100, 80,0.03);
Planet moon=new Planet(earth,"images/moon.png", 60, 40,0.03,true);
public void paint(Graphics g) {
//g.drawImage(img,Constants.FRAME_WIDTH/2-64,Constants.FRAME_HIGH/2-64,null);
sun.draw(g);
earth.draw(g);
mars.draw(g);
venus.draw(g);
moon.draw(g);
}






public static void main(String[] args) {
new MySolarFrame().LaunchFrame();
  


}


}

程序结束，欢迎大家批评指正，附整个程序的源代码：http://page92.ctfile.com/file/140761906