本人菜鸟想求教！为什么只有存款线程启动，取款线程没反应

[J5175]

package account;
public class Bank {
public static void main(String[] argos){

Account a=new Account("12345678",100);
PutMoney p=new PutMoney(a);
GetMoney g=new GetMoney(a);
Thread tp=new Thread(p);
Thread tg=new Thread(g);
tp.start();
tg.start();
}
}




class Account {
String ID;
double balance;
public Account(String strID,double b){
ID=strID;
balance=b;
}

public synchronized void putMoney(double money){

System.out.println("账号："+ID+"存入"+money);
balance +=money;
System.out.println("账号："+ID+" 余额"+balance);





}
public synchronized void subMoney(double money){

System.out.println("账号："+ID+" 取出"+money);
if(balance>money){
balance -=money;
System.out.println("账号："+ID+" 余额"+balance);
b=true;
}
else{
System.out.println("余额不足，取款失败！");
}
}}


class PutMoney implements Runnable{
Account a;

public PutMoney(Account a){

this.a=a;
}
public void run(){
for(int i=0;i<10;i++){
a.putMoney(Math.random()*1000);
}

}
}

class GetMoney implements Runnable{
Account a;

public GetMoney(Account a){

this.a=a;
}
public void run(){
for(int i=0;i<10;i++){
a.putMoney(Math.random()*1000);
}
}
}

[ufo1440]

[lihaigai11]

发错地方了？
另b=true; 哪来的b?

[zh2332926106]

GetMoney类的run方法调用subMoney而不是putMoney