关于 阿里巴巴笔试题 ：投资保险的 建议

/**
 * 
 * @author xy1131975903
 * 1)应该将保险类设计为资源共享，即设计一个同步方法用于控制用户的投资；推断是否投资成功；
 * 2)应将投资者设计为多线程类，即实现Runnable接口，能够竞争投资。
 * 3)须要在投资者中体现，竞争投资资源(保险类)的属性，即能够设计保险类为其成员变量。
 *   这样就能够体现多个用户竞争投资资源的实现。

 *
 */
class Insurance{
	private double yield=0.18;
	private int totalAmount=200000;
	private int minInvestment=1000;
	public int abAmount=0;
	private int count=0;
	public Insurance(){};
	
	public synchronized boolean buySuccess(int funds,String userID){
		boolean isSuccess=false;
		count++;
		System.out.println("投资： "+funds+"  ; 眼下剩余：  "+(totalAmount-abAmount));
		if(funds%minInvestment==0 && funds<=totalAmount-abAmount){
			abAmount+=funds;
			System.out.println("第"+count+"个用户 ("+userID+") success!");
			isSuccess=true;
		}else{
			System.out.println("第"+count+"个用户 ("+userID+") failed!");
		}
		System.out.println();
		return isSuccess;
	}
	
}
class User implements Runnable{
	private String userID=null;
	private int funds=0;
	private Insurance mInsurance=null;
	public boolean isSuccess=false;
	
	public boolean isRun=false;
	
	public User(String userID,int funds,Insurance mInsurance){
		this.userID=userID;
		this.mInsurance=mInsurance;
		this.funds=funds;
	}
	@Override
	public void run() {
		// TODO 自己主动生成的方法存根
		isSuccess=mInsurance.buySuccess(funds,userID);
		isRun=true;
	}
	public String getUserId(){return userID;}
	public int getFunds(){return funds;}
	
}
class TestInsuracne{
	public void test(){
		Insurance mInsurance=new Insurance();
		List<User>mList=new ArrayList<User>();
		User mUser[]=new User[20];
		Thread mt[]=new Thread[20];
		int i=0,sleeptime=0;
		for(i=0;i<mUser.length;i++){
			String str="userID_"+(i+1);
			mUser[i]=new User(str, (i+1)*1000, mInsurance);
			mt[i]=new Thread(mUser[i]);
			sleeptime=(int)Math.random()*5000;
			start(sleeptime, mt[i]);
		}
		
		//boolean exitFlag=false;
		while(true){
			for(i=0;i<mUser.length;i++){
				if(!mUser[i].isRun)break;
			}
			if(i==mUser.length)break;
		}
		System.out.println("具体数据例如以下:");
		for(i=0;i<mUser.length;i++){
			if(mUser[i].isSuccess){
				mList.add(mUser[i]);
			}
		}
		User tempUser=null;
		for(i=0;i<mList.size();i++){
			tempUser=(User)mList.get(i);
			System.out.println(tempUser.getUserId()+": "+tempUser.getFunds());
		}
	}
	public void start(int sleepTime,Thread mt){
		try {
			Thread.sleep(sleepTime);
			mt.start();
		} catch (InterruptedException e) {
			// TODO 自己主动生成的 catch 块
			e.printStackTrace();
		}
	}
}