线程问题求教！谢谢

public class SynchronizedClass1 extends Thread{
    private Account account;
    private double drawbalance;
    public SynchronizedClass1(String name,Account account,double drawbalance){
        super(name);
        this.account=account;
        this.drawbalance=drawbalance;
        start();
        
    }
    public void run(){
        for(int i=0;i<20;i++){
        try{sleep(1000);}catch(Exception e){}
        account.draw(drawbalance);}
    }
    public static void main(String[] args){
        Account a=new Account("刘腾",100000);
        new SynchronizedClass1("A线程",a,100);
        Thread rt=new Thread(new RunnableClass(a));
        rt.setName("B线程");
        rt.start();
    }
}
//账户
class Account {
    private String name;
    private double balance;
    public Account(){}
    public Account(String name,double balance){
        this.name=name;
        this.balance=balance;
    }
    public void setName(String name){
        this.name=name;
    }
    public void setBalance(double balance){
        this.balance=balance;
    }
    public String getName(){
        return name;
    }
    public double getBalance(){
        return balance;
    }
    public boolean equals(Object obj){
        if(this==obj)return true;
        if(obj!=null)return false;
        if(getClass()!=obj.getClass())return false;
        Account other =(Account) obj;
        if(other.name==name&&other.balance==balance)return true;
        else return false;
    }
    public synchronized void draw(double drawbalance ){
            if(drawbalance>getBalance()){
                System.out.println("余额不足！");
            }else{
                System.out.println("吐钱成功！");
                try{
                    Thread.sleep(1000);
                    setBalance(getBalance()-drawbalance);
                    System.out.println("余额为："+getBalance());
                }catch(Exception e){
                    System.out.println(e);
                }
            }
    }
}
class RunnableClass implements Runnable{
    private Account account;
    //private double drawbalance;
    public RunnableClass(Account account){
        this.account=account;    
    }
    public void run(){
        for(int k=0;k<15;k++){
        try{Thread.sleep(1000);
        System.out.println(account.getBalance());
        }catch(Exception e){}
        }
    }
}

问题：一个Account实例，传到两个线程中，一个线程（1）执行它的同步代码方法，另一个线程（2）执行它的普通方法。我在同步代码块中让其线程进入休眠。按理说只要进入同步代码块，这个类就被加锁了，另外一个线程不应该执行撒。为什么就在（1）休眠的状态下，（2）却执行了？求教！！！