问题：开户为10000，其中张三隔一段时间会存入100，李四会隔一段时间进行取款100，王五会过一段时间取款200，存入金额不能超过20000，当取款为0时，进行，如何保障该阶段的数据一致性问题
解决方案：将开户金额设置为atomic原子类，同时取款贷款设置为synchronized即可解决该问题
开户类Account
package com.currency.currency05;import lombok.Data;import java.util.concurrent.atomic.AtomicInteger;@Datapublic class Account { private String name; private AtomicInteger amount; public void name() { System.out.println("账户为：" + name + "!"); } public synchronized boolean deposit(String threadName, Integer change) { amount.addAndGet(change); if(amount.get() > 20000) { System.out.print("贷款金额曾经达到下限，贷款失败"); return false; } System.out.println("01：" + threadName+",贷款金额为"+change + ",开始贷款，贷款后余额为" + amount); return true; } public synchronized boolean withdraw(String threadName, Integer money) { if (amount.get() <= 0 || amount.get() < money) { System.out.println(threadName+",账户金额为"+amount.get()+"，你的取款金额为"+money+"，取款失败"); return false; } else { amount.addAndGet(-money); System.out.println("02：" + threadName+",取款金额为"+money + ",开始取款，取款后余额为" + amount); return true; } } public synchronized void openAccount(String name, Integer money) { this.name = name; this.amount = new AtomicInteger(money); System.out.println("00：" + name + "开户胜利,开户金额为"+money); }}取款类Deposit
package com.currency.currency05;import lombok.Data;import java.util.Random;@Datapublic class Deposit implements Runnable{ private Account account; private int deposit; public void deposit(Account account, int deposit) { this.account = account; this.deposit = deposit; } @Override public void run() { String threadName = Thread.currentThread().getName(); while (true) { if (account.getAmount().get() < 20000) { boolean isFlag = account.deposit(threadName, deposit); if (!isFlag) { break; } try { Thread.sleep(new Random().nextInt(1000)); } catch (InterruptedException e) { e.printStackTrace(); } } if (account.getAmount().get() >= 20000) { break; } if (account.getAmount().get() == 0) { System.out.println("余额为零，贷款完结"); break; } } }}贷款类Withdraw
package com.currency.currency05;import java.util.Random;/** * @author huanglaoxie(微信:yfct-8888) * @className Withdraw * @description： * @date 2017/12/20 10:16 */public class Withdraw implements Runnable{ private Account account; private int withdraw; public void withdraw(Account account, int withdraw) { this.account = account; this.withdraw = withdraw; } @Override public void run() { String threadName = Thread.currentThread().getName(); while (true) { if (account.getAmount().get() > 0) { boolean isFlag = account.withdraw(threadName, withdraw); if (!isFlag) { break; } try { Thread.sleep(new Random().nextInt(1000)); } catch (InterruptedException e) { e.printStackTrace(); } } else { break; } } }}线程执行
package com.currency.currency05;public class Test { public static void main(String[] args) { Account account = new Account(); account.openAccount("zhouzhou", 10000); Deposit p1 = new Deposit(); p1.deposit(account, 100); Thread depositThread = new Thread(p1, "张三"); Withdraw p2 = new Withdraw(); p2.withdraw(account, 100); Thread withdrawThread1 = new Thread(p2, "李四"); Withdraw p3 = new Withdraw(); p3.withdraw(account, 200); Thread withdrawThread2 = new Thread(p3, "王五"); withdrawThread1.start(); withdrawThread2.start(); depositThread.start(); }}测试后果
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com.currency.currency05.Test00：zhouzhou开户胜利,开户金额为1000002：李四,取款金额为100,开始取款，取款后余额为990001：张三,贷款金额为100,开始贷款，贷款后余额为1000002：王五,取款金额为200,开始取款，取款后余额为980002：王五,取款金额为200,开始取款，取款后余额为960001：张三,贷款金额为100,开始贷款，贷款后余额为970002：李四,取款金额为100,开始取款，取款后余额为960002：王五,取款金额为200,开始取款，取款后余额为940001：张三,贷款金额为100,开始贷款，贷款后余额为950001：张三,贷款金额为100,开始贷款，贷款后余额为960002：王五,取款金额为200,开始取款，取款后余额为940002：王五,取款金额为200,开始取款，取款后余额为920002：李四,取款金额为100,开始取款，取款后余额为910002：王五,取款金额为200,开始取款，取款后余额为890001：张三,贷款金额为100,开始贷款，贷款后余额为900002：李四,取款金额为100,开始取款，取款后余额为890002：王五,取款金额为200,开始取款，取款后余额为870002：李四,取款金额为100,开始取款，取款后余额为860002：李四,取款金额为100,开始取款，取款后余额为850002：王五,取款金额为200,开始取款，取款后余额为830001：张三,贷款金额为100,开始贷款，贷款后余额为840002：李四,取款金额为100,开始取款，取款后余额为830002：李四,取款金额为100,开始取款，取款后余额为820002：王五,取款金额为200,开始取款，取款后余额为800001：张三,贷款金额为100,开始贷款，贷款后余额为810002：李四,取款金额为100,开始取款，取款后余额为800001：张三,贷款金额为100,开始贷款，贷款后余额为810002：王五,取款金额为200,开始取款，取款后余额为790002：李四,取款金额为100,开始取款，取款后余额为780001：张三,贷款金额为100,开始贷款，贷款后余额为790002：王五,取款金额为200,开始取款，取款后余额为770001：张三,贷款金额为100,开始贷款，贷款后余额为780002：李四,取款金额为100,开始取款，取款后余额为770001：张三,贷款金额为100,开始贷款，贷款后余额为780002：李四,取款金额为100,开始取款，取款后余额为770002：李四,取款金额为100,开始取款，取款后余额为760001：张三,贷款金额为100,开始贷款，贷款后余额为770002：王五,取款金额为200,开始取款，取款后余额为750002：李四,取款金额为100,开始取款，取款后余额为740002：李四,取款金额为100,开始取款，取款后余额为730001：张三,贷款金额为100,开始贷款，贷款后余额为740001：张三,贷款金额为100,开始贷款，贷款后余额为750002：李四,取款金额为100,开始取款，取款后余额为740002：王五,取款金额为200,开始取款，取款后余额为720002：王五,取款金额为200,开始取款，取款后余额为700002：王五,取款金额为200,开始取款，取款后余额为680001：张三,贷款金额为100,开始贷款，贷款后余额为690002：李四,取款金额为100,开始取款，取款后余额为680002：王五,取款金额为200,开始取款，取款后余额为660001：张三,贷款金额为100,开始贷款，贷款后余额为670002：王五,取款金额为200,开始取款，取款后余额为650002：李四,取款金额为100,开始取款，取款后余额为640001：张三,贷款金额为100,开始贷款，贷款后余额为650001：张三,贷款金额为100,开始贷款，贷款后余额为660002：李四,取款金额为100,开始取款，取款后余额为650001：张三,贷款金额为100,开始贷款，贷款后余额为660002：王五,取款金额为200,开始取款，取款后余额为640002：李四,取款金额为100,开始取款，取款后余额为630001：张三,贷款金额为100,开始贷款，贷款后余额为640001：张三,贷款金额为100,开始贷款，贷款后余额为650002：李四,取款金额为100,开始取款，取款后余额为640002：王五,取款金额为200,开始取款，取款后余额为620002：李四,取款金额为100,开始取款，取款后余额为610002：李四,取款金额为100,开始取款，取款后余额为600001：张三,贷款金额为100,开始贷款，贷款后余额为610002：王五,取款金额为200,开始取款，取款后余额为590002：王五,取款金额为200,开始取款，取款后余额为570002：李四,取款金额为100,开始取款，取款后余额为560001：张三,贷款金额为100,开始贷款，贷款后余额为570002：李四,取款金额为100,开始取款，取款后余额为560002：王五,取款金额为200,开始取款，取款后余额为540001：张三,贷款金额为100,开始贷款，贷款后余额为550001：张三,贷款金额为100,开始贷款，贷款后余额为560002：王五,取款金额为200,开始取款，取款后余额为540002：王五,取款金额为200,开始取款，取款后余额为520002：李四,取款金额为100,开始取款，取款后余额为510002：李四,取款金额为100,开始取款，取款后余额为500001：张三,贷款金额为100,开始贷款，贷款后余额为510002：王五,取款金额为200,开始取款，取款后余额为490002：李四,取款金额为100,开始取款，取款后余额为480002：王五,取款金额为200,开始取款，取款后余额为460001：张三,贷款金额为100,开始贷款，贷款后余额为470002：李四,取款金额为100,开始取款，取款后余额为460002：王五,取款金额为200,开始取款，取款后余额为440002：李四,取款金额为100,开始取款，取款后余额为430001：张三,贷款金额为100,开始贷款，贷款后余额为440001：张三,贷款金额为100,开始贷款，贷款后余额为450002：王五,取款金额为200,开始取款，取款后余额为430002：李四,取款金额为100,开始取款，取款后余额为420002：王五,取款金额为200,开始取款，取款后余额为400002：李四,取款金额为100,开始取款，取款后余额为390002：李四,取款金额为100,开始取款，取款后余额为380001：张三,贷款金额为100,开始贷款，贷款后余额为390001：张三,贷款金额为100,开始贷款，贷款后余额为400002：王五,取款金额为200,开始取款，取款后余额为380001：张三,贷款金额为100,开始贷款，贷款后余额为390002：李四,取款金额为100,开始取款，取款后余额为380002：王五,取款金额为200,开始取款，取款后余额为360002：李四,取款金额为100,开始取款，取款后余额为350002：王五,取款金额为200,开始取款，取款后余额为330002：王五,取款金额为200,开始取款，取款后余额为310002：李四,取款金额为100,开始取款，取款后余额为300001：张三,贷款金额为100,开始贷款，贷款后余额为310002：李四,取款金额为100,开始取款，取款后余额为300002：王五,取款金额为200,开始取款，取款后余额为280001：张三,贷款金额为100,开始贷款，贷款后余额为290001：张三,贷款金额为100,开始贷款，贷款后余额为300001：张三,贷款金额为100,开始贷款，贷款后余额为310002：王五,取款金额为200,开始取款，取款后余额为290002：李四,取款金额为100,开始取款，取款后余额为280002：王五,取款金额为200,开始取款，取款后余额为260001：张三,贷款金额为100,开始贷款，贷款后余额为270001：张三,贷款金额为100,开始贷款，贷款后余额为280001：张三,贷款金额为100,开始贷款，贷款后余额为290002：李四,取款金额为100,开始取款，取款后余额为280001：张三,贷款金额为100,开始贷款，贷款后余额为290002：王五,取款金额为200,开始取款，取款后余额为270001：张三,贷款金额为100,开始贷款，贷款后余额为280002：李四,取款金额为100,开始取款，取款后余额为270002：王五,取款金额为200,开始取款，取款后余额为250001：张三,贷款金额为100,开始贷款，贷款后余额为260002：王五,取款金额为200,开始取款，取款后余额为240002：王五,取款金额为200,开始取款，取款后余额为220002：李四,取款金额为100,开始取款，取款后余额为210002：李四,取款金额为100,开始取款，取款后余额为200002：王五,取款金额为200,开始取款，取款后余额为180001：张三,贷款金额为100,开始贷款，贷款后余额为190002：李四,取款金额为100,开始取款，取款后余额为180002：王五,取款金额为200,开始取款，取款后余额为160001：张三,贷款金额为100,开始贷款，贷款后余额为170001：张三,贷款金额为100,开始贷款，贷款后余额为180002：王五,取款金额为200,开始取款，取款后余额为160002：李四,取款金额为100,开始取款，取款后余额为150001：张三,贷款金额为100,开始贷款，贷款后余额为160002：王五,取款金额为200,开始取款，取款后余额为140001：张三,贷款金额为100,开始贷款，贷款后余额为150002：王五,取款金额为200,开始取款，取款后余额为130002：王五,取款金额为200,开始取款，取款后余额为110001：张三,贷款金额为100,开始贷款，贷款后余额为120002：李四,取款金额为100,开始取款，取款后余额为110002：王五,取款金额为200,开始取款，取款后余额为90002：王五,取款金额为200,开始取款，取款后余额为70001：张三,贷款金额为100,开始贷款，贷款后余额为80002：李四,取款金额为100,开始取款，取款后余额为70002：王五,取款金额为200,开始取款，取款后余额为50001：张三,贷款金额为100,开始贷款，贷款后余额为60002：李四,取款金额为100,开始取款，取款后余额为50002：王五,取款金额为200,开始取款，取款后余额为30002：李四,取款金额为100,开始取款，取款后余额为20001：张三,贷款金额为100,开始贷款，贷款后余额为30002：李四,取款金额为100,开始取款，取款后余额为20002：王五,取款金额为200,开始取款，取款后余额为0余额为零，贷款完结Process finished with exit code 0