Java多线程导致的线程安全问题的实例解决

package m11.d20;

import java.util.Random;
/*
单用户同时存钱取钱的多线程解决线程安全问题解决的实例
 */
public class BankTest {
    public static BankAccount acct=new BankAccount("张三",10000);
    public static void main(String[] args) {
        new Thread(new BankPutMoney()).start();
        new Thread(new BankGetMoney()).start();
    }
}
class BankAccount{
    private static int init_id=1000;
    private int id;
    private double balance=0;
    private String name="Jack";
    public double succGetMoney=0;
    public double succPutMoney=0;
    public BankAccount(){
        this.id=init_id++;
        this.init();
    }
    public BankAccount( String name,double money ){
        this.id=init_id++;
        this.name=name;
        this.balance=money;
        this.init();
    }
    private void init(){
        System.out.println("创建账户成功！当前账户ID为："+this.id+"，用户名为："+this.name+"，当前账户可用余额为"+this.balance+"元");
    }
    public void printBalance(){
        System.out.println("账户："+this.id+"，可用余额为："+this.balance+"元");
    }
    public synchronized void putMoney(double money){
        this.balance+=money;
        System.out.println("存款"+money+"元成功！账户："+this.id+"，用户余额为"+this.balance+"元");
        BankTest.acct.succPutMoney+=money;
    }
    public synchronized void getMoney(double money){
        if( this.balance-money<0 ){
            System.out.println("取款失败！余额不足导致的失败交易！");
        }else{
            this.balance-=money;
            System.out.println("取款成功！本次取款"+money+"元，当前可用余额为"+this.balance+"元");
            BankTest.acct.succGetMoney+=money;
        }
    }
    public double getBalance(){
        return this.balance;
    }

}
class BankPutMoney implements Runnable{
    @Override
    public void run() {
        int i=0;
        while (i<20){
            try {
                Thread.sleep(100);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            BankTest.acct.putMoney((int)(Math.random()*5000+100));
            i++;
        }
        System.out.println("所有存款操作完成，当前余额为"+BankTest.acct.getBalance()+"元");
        System.out.println("截止当前，成功存款："+BankTest.acct.succPutMoney+"元，成功取款："+BankTest.acct.succGetMoney+"元");
    }
}
class BankGetMoney implements Runnable{
    @Override
    public void run() {
        int i=0;
        while (i<20){
            try {
                Thread.sleep(100);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            BankTest.acct.getMoney((int)(Math.random()*5000+100));
            i++;
        }
        System.out.println("所有取款操作完成，当前余额为"+BankTest.acct.getBalance()+"元");
        System.out.println("截止当前，成功存款："+BankTest.acct.succPutMoney+"元，成功取款："+BankTest.acct.succGetMoney+"元");
    }
}