多线程取钱
public class DrawDemo {
public static void main(String[] args) {
Account account = new Account("12347866", 1000);
DrawThread d = new DrawThread(account, "张三", 800);
DrawThread d1 = new DrawThread(account, "李四", 100);
DrawThread d2= new DrawThread(account, "王五", 400);
d.start();
d1.start();
d2.start();
}
}
//2.取现的线程
public class DrawThread extends Thread {
private Account account;
private double drawAmount;
public DrawThread(Account account, String name, double drawAmount){
super(name);
this.account = account;
this.drawAmount = drawAmount;
}
@Override
public void run() {
synchronized (account) {
if(account.getBalance() > drawAmount && account.getBalance() >= 0) {
System.out.println("余额足够, "+ Thread.currentThread().getName()+"取出"+ drawAmount + "元");
try{
Thread.sleep(1000);
}catch(Exception e){
e.printStackTrace();
}
account.setBalance((account.getBalance() - drawAmount));
System.out.println("余额还剩:" + (account.getBalance()));
}else{
System.out.println("余额不足,取钱失败!!!");
}
}
}
}
//3. 实体类
public class Account {
private String accountNo;
private double balance;
public Account(){}
public Account(String accountNo, double balance){
this.accountNo = accountNo;
this.balance = balance;
}
public String getAccountNo() {
return accountNo;
}
public void setAccountNo(String accountNo) {
this.accountNo = accountNo;
}
public double getBalance() {
return balance;
}
public void setBalance(double balance) {
this.balance = balance;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result
+ ((accountNo == null) ? 0 : accountNo.hashCode());
long temp;
temp = Double.doubleToLongBits(balance);
result = prime * result + (int) (temp ^ (temp >>> 32));
return result;
}
@Override
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 (accountNo == null) {
if (other.accountNo != null)
return false;
} else if (!accountNo.equals(other.accountNo))
return false;
if (Double.doubleToLongBits(balance) != Double
.doubleToLongBits(other.balance))
return false;
return true;
}
第二种方式: 控制共享资源
//1. 实体类中做文章, 做成同步的方法
public class Account {
private String accountNo;
private double balance;
public Account(){}
public Account(String accountNo, double balance){
this.accountNo = accountNo;
this.balance = balance;
}
public String getAccountNo() {
return accountNo;
}
public void setAccountNo(String accountNo) {
this.accountNo = accountNo;
}
public double getBalance() {
return balance;
}
public void setBalance(double balance) {
this.balance = balance;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result
+ ((accountNo == null) ? 0 : accountNo.hashCode());
long temp;
temp = Double.doubleToLongBits(balance);
result = prime * result + (int) (temp ^ (temp >>> 32));
return result;
}
@Override
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 (accountNo == null) {
if (other.accountNo != null)
return false;
} else if (!accountNo.equals(other.accountNo))
return false;
if (Double.doubleToLongBits(balance) != Double
.doubleToLongBits(other.balance))
return false;
return true;
}
public synchronized void drawMoney(double drawAmount){
System.out.println(Thread.currentThread().getName()+ "客户来了....想取"+drawAmount);
if(balance - drawAmount > 0){
System.out.println(Thread.currentThread().getName()+"取出:" + drawAmount);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
balance -= drawAmount;
System.out.println("还剩:" + balance);
} else{
System.out.println("余额不足取现失败");
}
}
}
//2. 取现线程
public class DrawThread extends Thread {
private Account account;
private double drawAmount;
public DrawThread(Account account, String name, double drawAmount){
super(name);
this.account = account;
this.drawAmount = drawAmount;
}
@Override
public void run() {
account.drawMoney(drawAmount);
}
}
//3.测试
public class DrawDemo {
public static void main(String[] args) {
Account account = new Account("12347866", 1000);
DrawThread d = new DrawThread(account, "张三", 800);
DrawThread d1 = new DrawThread(account, "李四", 100);
DrawThread d2= new DrawThread(account, "王五", 400);
d.start();
d1.start();
d2.start();
}
}
//第三种方式, 改写成实现Runnable接口
//1. 测试开始
public class DrawDemo {
public static void main(String[] args) {
Account account = new Account("12347866", 1000);
DrawThread d = new DrawThread(account, 800);
DrawThread d1 = new DrawThread(account, 200);
DrawThread d2 = new DrawThread(account, 100);
Thread t1 = new Thread(d, "孙悟空");
Thread t2 = new Thread(d1, "猪八戒");
Thread t3 = new Thread(d2, "小白龙");
t1.start();
t2.start();
t3.start();
}
}
//2. 取现线程
public class DrawThread implements Runnable {
private Account account;
private double drawAmount;
public DrawThread(Account account, double drawAmount){
this.account = account;
this.drawAmount = drawAmount;
}
@Override
public void run() {
synchronized (account) {
if(account.getBalance() > drawAmount && account.getBalance() >= 0) {
System.out.println("余额足够, "+ Thread.currentThread().getName()+"取出"+ drawAmount + "元");
try{
Thread.sleep(1000);
}catch(Exception e){
e.printStackTrace();
}
account.setBalance((account.getBalance() - drawAmount));
System.out.println("余额还剩:" + (account.getBalance()));
}else{
System.out.println("余额不足,取钱失败!!!");
}
}
// account.drawMoney(drawAmount);
}
}
//3.实体类--共享资源
public class Account {
private String accountNo;
private double balance;
public Account(){}
public Account(String accountNo, double balance){
this.accountNo = accountNo;
this.balance = balance;
}
public String getAccountNo() {
return accountNo;
}
public void setAccountNo(String accountNo) {
this.accountNo = accountNo;
}
public double getBalance() {
return balance;
}
public void setBalance(double balance) {
this.balance = balance;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result
+ ((accountNo == null) ? 0 : accountNo.hashCode());
long temp;
temp = Double.doubleToLongBits(balance);
result = prime * result + (int) (temp ^ (temp >>> 32));
return result;
}
@Override
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 (accountNo == null) {
if (other.accountNo != null)
return false;
} else if (!accountNo.equals(other.accountNo))
return false;
if (Double.doubleToLongBits(balance) != Double
.doubleToLongBits(other.balance))
return false;
return true;
}
// public synchronized void drawMoney(double drawAmount){
// System.out.println(Thread.currentThread().getName()+ "客户来了....想取"+drawAmount);
// if(balance - drawAmount > 0){
// System.out.println(Thread.currentThread().getName()+"取出:" + drawAmount);
// try {
// Thread.sleep(1000);
// } catch (InterruptedException e) {
// e.printStackTrace();
// }
// balance -= drawAmount;
// System.out.println("还剩:" + balance);
//
// } else{
// System.out.println("余额不足取现失败");
// }
// }
}
第四种: 通过ReentranLock来同步
//其他地方同前面一样
package com.ckang.drawmoney;
import java.util.concurrent.locks.ReentrantLock;
public class Account {
private final ReentrantLock lock = new ReentrantLock();
private String accountNo;
private double balance;
public Account(){}
public Account(String accountNo, double balance){
this.accountNo = accountNo;
this.balance = balance;
}
public String getAccountNo() {
return accountNo;
}
public void setAccountNo(String accountNo) {
this.accountNo = accountNo;
}
public double getBalance() {
return balance;
}
public void setBalance(double balance) {
this.balance = balance;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result
+ ((accountNo == null) ? 0 : accountNo.hashCode());
long temp;
temp = Double.doubleToLongBits(balance);
result = prime * result + (int) (temp ^ (temp >>> 32));
return result;
}
@Override
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 (accountNo == null) {
if (other.accountNo != null)
return false;
} else if (!accountNo.equals(other.accountNo))
return false;
if (Double.doubleToLongBits(balance) != Double
.doubleToLongBits(other.balance))
return false;
return true;
}
public void drawMoney(double drawAmount){
lock.lock();
try{
System.out.println(Thread.currentThread().getName()+ "客户来了....想取"+drawAmount);
if(balance - drawAmount > 0){
System.out.println(Thread.currentThread().getName()+"取出:" + drawAmount);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
balance -= drawAmount;
System.out.println("还剩:" + balance);
} else{
System.out.println("余额不足取现失败");
}
}finally{
lock.unlock();
}
}
}
