Java多线程之对写业务加锁，对读业务不加锁，会产生脏读

import java.util.concurrent.TimeUnit;

/**
 * 对写业务加锁
 * 对读业务不加锁
 * 脏读
 */
public class Account {

    String name;
    double balance;

    public synchronized void set(String name, double balance) {
        this.name = name;
        try {
            Thread.sleep(2000); //写线程休眠两秒
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        this.balance = balance;
    }

    /**
     * 解决脏读在方法上加synchronized
     * @param name
     * @return
     */
    public /*synchronized*/ double getBalance(String name) {
        return this.balance;
    }

    public static void main(String[] args) {

        Account account = new Account();
        new Thread(() -> account.set("张三", 100.0)).start();

        try {
            TimeUnit.SECONDS.sleep(1); //读线程休眠一秒
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        System.out.println(account.getBalance("张三"));

        try {
            TimeUnit.SECONDS.sleep(2); //读线程休眠两秒
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        System.out.println(account.getBalance("张三"));

    }

}