大球吃小球

Ball.java

package day7;

import java.awt.Color;
import java.awt.Graphics;



public class Ball {
	int x,y;
	int d;
	Color ballColor;
	int speed;
	int position;
	/*小球运动方向*/
	public static final int LEFT_UP=0;
	public static final int RIGHT_UP=1;
	public static final int LEFT_DOWN=2;
	public static final int RIGHT_DOWN=3;
	public Ball(int x,int y,int d,Color ballColor,int speed,int position){
		this.x=x;
		this.y=y;
		this.d=d;
		this.ballColor=ballColor;
		this.speed=speed;
		this. position=position;
	}
	
	//画小球
	public void drawBall(Graphics g){
		g.setColor(ballColor);
		g.fillOval(x, y, d, d);
		
		
	}
	//小球运动方向
	public void ballMove(){
		switch(this.position){
		case LEFT_UP:
			x-=speed;
			y-=speed;
			if(x<=0){
				this.position=RIGHT_UP;
			}else if(y<=0){
				this.position=LEFT_DOWN;
			}
			
			break;
		case RIGHT_UP:
			x+=speed;
			y-=speed;
			if(x>=700){
				this.position=LEFT_UP;
			}else if (y<=0) {
				this.position=RIGHT_DOWN;
				
			}
			
			break;
		case LEFT_DOWN:
			x-=speed;
			y+=speed;
			if (x<=0) {
				this.position=RIGHT_DOWN;
			}else if (y>=470) {
				this.position=LEFT_UP;
				
			}
			
			break;
		case RIGHT_DOWN:
			x+=speed;
			y+=speed;
			if (x>=700) {
				this.position=LEFT_DOWN;
				
			}else if (y>=470) {
				this.position=RIGHT_UP;
				
			}
			
			break;
		}
		
	}

}

BallMain.java

package day7;

import java.awt.Dimension;
import java.awt.Toolkit;

import javax.swing.JFrame;

import day2.TJPanel;

public class BallMain extends JFrame {
	//屏幕的宽高设置
	public static final int SCREEN_WIDTH=750;
	public static final int SCREEN_HEIGHT=550;
	//
	Dimension d=Toolkit.getDefaultToolkit().getScreenSize();
	int width=(int)d.getWidth();
	int height=(int)d.getHeight();
	
	/*构造方法*/
	public BallMain(){
		this.setTitle("V1.0");
		//this.setBounds(0, 0, width, height);
		this.setBounds(100, 100, SCREEN_WIDTH, SCREEN_HEIGHT);
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
		//添加小球到窗体上
		BallJPanel bj=new BallJPanel();
		this.add(bj);
		
		this.setVisible(true);//显示窗体,调用paint方法
		bj.startBalls();
	}

	public static void main(String[] args) {
		new BallMain();
		
		

	}

}

BallJPanel.java

package day7;

import java.awt.Color;
import java.awt.Graphics;
import java.util.List;
import java.util.ArrayList;

import javax.swing.JPanel;

import sun.awt.RepaintArea;




public class BallJPanel extends JPanel {
	//存储小球的集合
	List<Ball> ballList=new ArrayList<Ball>();
	//小球数量
	private int ballNumber=50;
	public BallJPanel(){
		addBall();
			
		}
			
	
	
	//产生小球的方法
	public void addBall(){
		for(int i=0;i<ballNumber;i++){
			int x=(int) (Math.random()*BallMain.SCREEN_WIDTH);
			int y=(int) (Math.random()*BallMain.SCREEN_HEIGHT);
			int position=(int) (Math.random()*4);
			//int d=(int) (Math.random()*15+1);
			int d=50;
			int speed=(int) (Math.random()*50);
			//int speed=50;
			//颜色 rgb
			int red=(int) (Math.random()*255+1);
			int green=(int) (Math.random()*255+1);
			int blue=(int) (Math.random()*255+1);
			Color ballColor=new Color(red,green,blue);
			Ball b=new Ball(x, y, d, ballColor, speed, position);
			//将小球添加到集合中
			ballList.add(b);}
		
	}
	public void paint(Graphics g){
		super.paint(g);
		
		for(int i=0;i<ballList.size();i++){
			Ball ball=ballList.get(i);
			ball.drawBall(g);
			/*g.setColor(ball.ballColor);
		g.fillOval(ball.x,ball.y,ball.d,ball.d);*/}
	}
	//小球运动
	public void startBalls(){
		//启动线程------匿名内部类
		new Thread(){
			public void run() {
				while (true) {
					//1.遍历小球集合
					for(int i=0;i<ballList.size();i++){
					//2.取出每一个小球
							Ball b=ballList.get(i);
					//3.让每一个小球移动
							b.ballMove();
					
				}
				for (int i = 0; i < ballList.size(); i++) {
					Ball b1=ballList.get(i);
					for (int j = i+1; j < ballList.size(); j++) {
						Ball b2=ballList.get(j);
						BallAndBall bab=new BallAndBall();
						bab.ballCrach(b1, b2);
						/*if (bab.isballCrach(b1, b2)) {
							if (b1.d>=b2.d) {
								b1.d+=b2.d/3;
								ballList.remove(b2);
								break;
								
							}else if (b2.d>=b1.d) {
								b2.d+=b1.d/3;
								ballList.remove(b1);
								break;
								
							}
						}*/
					}
					
				}	
					
					
					
				try {
					Thread.sleep(200);
					
				} catch (Exception e) {
					// TODO: handle exception
				}
				repaint();
				}}
	
			}.start();
		}
	


}
	
	
	
	
	
	
	
	
	
	
	
	
	
	

BallAndBall.java

package day7;

public class BallAndBall {
	public void ballCrach(Ball b1,Ball b2){
		int x1=b1.x+b1.d/2;
		int y1=b1.y+b1.d/2;
		int x2=b2.x+b2.d/2;
		int y2=b2.y+b2.d/2;
		//计算圆心距
		double e=Math.sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
		
		//如果碰撞上
		if (e<=b1.d/2+b2.d/2) {
			switch (b1.position) {
			case Ball.LEFT_UP:
				b1.position=Ball.RIGHT_DOWN;
				break;
			case Ball.RIGHT_UP:
				b1.position=Ball.LEFT_DOWN;
				break;
			case Ball.LEFT_DOWN:
				b1.position=Ball.RIGHT_UP;
				break;
			case Ball.RIGHT_DOWN:
				b1.position=Ball.LEFT_UP;
				break;
				}
			switch (b2.position) {
			case Ball.LEFT_UP:
				b2.position=Ball.RIGHT_DOWN;
				break;
			case Ball.RIGHT_UP:
				b2.position=Ball.LEFT_DOWN;
				break;
			case Ball.LEFT_DOWN:
				b2.position=Ball.RIGHT_UP;
				break;
			case Ball.RIGHT_DOWN:
				b2.position=Ball.LEFT_UP;
				break;
			}}
			
		}
		//检测碰撞
		public boolean isballCrach(Ball b1,Ball b2){
			boolean flag=false;
			int x1=b1.x+b1.d/2;
			int x2=b1.x+b2.d/2;
			int y1=b1.y+b1.d/2;
			int y2=b1.y+b2.d/2;
			//计算圆心距
			double e=Math.sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
			
			//如果碰撞上
			if (e<=b1.d/2+b2.d/2) {
				return true;
			}
			return false;
		
		
		
		
	}

}