绘制随机小球来回弹动java代码.doc

Java小球碰撞代码 绘制小球随机位置，随机颜色（自定义颜色）来回碰撞。这个代码只有上下左右四个方向，所以反弹也是固定的45°角。 首先是定义小球（Ball类） package picture; import java.awt.Color; import java.awt.Graphics; public class Ball { private int x,y;//分清定义是左上角顶点坐标还是圆心点坐标（圆心坐标） private int rSize;//半径 private Color color; private int speed; private int orientation; private BallPanel panel;//获得小球所属的面板 public static final int RIGHT_DOWN=0; public static final int RIGHT_ON=1; public static final int LEFT_DOWN=2; public static final int LEFT_ON=3; public Ball(){ } public Ball(int x, int y, int rSize, Color color, int speed, int orientation) { super(); this.x = x; this.y = y; this.rSize = rSize; this.color = color; this.speed = speed; this.orientation = orientation; } public void draw(Graphics g){ g.setColor(color); g.fillArc(x-rSize, y-rSize/*左上角定点坐标*/, 2*rSize, 2*rSize, 0, 360); }//定义小球绘画的逻辑 public void move(){//小球处在不同方向时移动所改变的坐标值 switch(orientation){ case RIGHT_DOWN: x+=speed;y+=speed; if(x+rSize =panel.getWidth()){ this.orientation = LEFT_DOWN; } if(y+rSize =panel.getHeight()){ this.orientation = RIGHT_ON; } break; case RIGHT_ON: x+=speed;y-=speed; if(x+rSize =panel.getWidth()){ this.orientation = LEFT_ON; } if(y-rSize = 0 ){ this.orientation = RIGHT_DOWN; } break; case LEFT_DOWN: x-=speed;y+=speed; if(x-rSize = 0 ){ this.orientation = RIGHT_DOWN; } if(y+rSize =panel.getHeight()){ this.orientation = LEFT_ON; } break; case LEFT_ON: x-=speed;y-=speed; if(x-rSize = 0 ){ this.orientation = RIGHT_ON; } if(y-rSize = 0){ this.orientation = LEFT_DOWN; } break; } /*碰到边界事件处理*/ } public int getX() { return x; } public void setX(int x) { this.x = x; } public int getY() { return y; } public void setY(int y) { this.y = y; } public int getrSize() { return rSize; } public void setrSize(int rSize) { this.rSize = rSize; } public Color getColor(