//DepositInBank.java
public class DepositInBank
{
 public static void main(String[] args)
{
 	 BankAccount ba=new BankAccount();//创建一个银行帐户ba
 ThreadGroup tg=new ThreadGroup("BankClient Group");
for(int i=0;i<5;i++){//模拟5位银行客户同时操作帐户ba
 	 Thread t=new Thread(tg,new BankClient(ba));
 	 t.start();
 	 }
 	 while(tg.activeCount()!=0){}
 	 //操作结束后统计帐户ba的余额
 	 System.out.println("BankAccount balance is:"+ba.getBalance());
 }
}
class BankAccount 
{ //银行帐户类
 private int balance; //余额属性
 BankAccount()
 {
 	balance=0;
 }
 int getBalance()
 {return balance;}
 void add() //向帐户汇款1000元
 {
 int newBalance=balance+1000;
 	try
 	{Thread.sleep(1);} //这里用Thread.sleep(1)语句模拟银行交易处理的延迟
 	catch(InterruptedException e)
 	{System.out.println(e);}
 	balance=newBalance;
 }
}
class BankClient extends Thread //银行客户类,每个客户都持有一个帐户
{
 	BankAccount ba;
 	BankClient(BankAccount ba)
 	{
 		this.ba=ba;
 }
 	public void run() //客户的行为,向帐户汇款
 	{
 	 ba.add();
 	}
}