python与Java线程实现方式的对比
1. python多线程的实现方式：
- 继承Thread类
- 实现Runnable接口
Callable接口+FutureTask包装器来创建Thread线程
线程操作涉及到的方法：
Thread：start启动 join加入新线程
Lock/Rock:acquire():加锁 release(): 释放锁
Condition：acquire():加锁 release(): 释放锁 wait notify notify_all
Event: set()等同于notify_all clear() 取消notify_all
time: sleep
timer:Timer(interval function args=[] kwargs={})interval: 指定的时间
- function: 要执行的方法
- args/kwargs: 方法的参数
2.Java多线程的实现方式：
- 继承Thread类实现多线程
- 实现Runnable接口方式实现多线程
- 通过 Callable 和 Future 创建线程。
线程操作涉及到的方法：
start() 、stop() (过时) 、join() 、wait() 、sleep() 、notify() 、notifyAll()
Java多线程方法详解
经典案例
共有四个和尚
其中一个和尚负责做馒头
其他三个和尚吃馒头
要求
当做馒头的时候，不能吃馒头
当吃馒头的时候不能做馒头
馒头上线只能是30个
在吃馒头的时候不能出现一个馒头被多个和尚吃
不能出现吃的时候和尚吃出异常（如一个和尚永远也吃不到，或者 一个和尚吃了一个不存在的馒头）
Java代码：
package com.dsj101.thread;
import java.util.ArrayList;
import java.util.List;
public class Test {
static class ManTou{
private int num;
public ManTou(int num) {
this.num = num;
}
@Override
public String toString() {
return "第"+num+"个";
}
}
public static List<ManTou> manTous=new ArrayList<>();
public static void main(String[] args) {
new HuoFu("大头和尚").start();
new ChiHuo("白眉和尚").start();
new ChiHuo("牛鼻子和尚").start();
new ChiHuo("花和尚").start();
}
//火夫
static class HuoFu extends Thread{
private String name;
public HuoFu(String name) {
this.name = name;
}
@Override
public void run() {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
while (true) {
synchronized ("a") {
System.out.println(name + "开始蒸馒头");
for (int i = 0; i < 30; i++) {
manTous.add(new ManTou(i + 1));
System.out.println("做完第" + (i + 1) + "个码头");
try {
Thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
System.out.println("馒头做好了，开始吃吧");
"a".notifyAll();
}
synchronized ("b") {
try {
System.out.println("我先去睡一会，没了叫我");
"b".wait();
System.out.println("我知道了开始做去");
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
//吃货
static class ChiHuo extends Thread{
private String name;
public ChiHuo(String name) {
this.name = name;
}
@Override
public void run() {
synchronized ("a"){
try {
"a".wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
ManTou m=null;
while (true) {
synchronized ("a") {
System.out.println(name + "开始吃馒头");
if (manTous.size() != 0) {
m = manTous.remove(0);
} else {
System.out.println(name + "发现没有馒头，叫醒火夫做馒头");
synchronized ("b"){
"b".notify();
}
try {
System.out.println("我等着呢，完事后叫我吃");
"a".wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
if (m != null) {
System.out.println(name + "消化馒头"+m.toString());
int rd = (int) (Math.random() * 2000 + 1000);
m = null;
try {
Thread.sleep(rd);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
} python代码：
import threading
import time
mantous=[]
a=threading.Lock()
b=threading.Lock()
ca=threading.Condition(a)
cb=threading.Condition(b)
#火夫的任务函数
def huofu(name):
time.sleep(1)
while True:
ca.acquire()
for i in range(1,31):
mantous.append("第{0}个馒头".format(i))
print("做好第{0}个馒头".format(i))
time.sleep(0.1)
print("馒头做好，叫醒吃货")
ca.notify_all()
ca.release()
print("{0}去等到".format(name))
cb.acquire()
cb.wait()
cb.release()
#吃货的任务函数
def chihuo(name):
ca.acquire()
ca.wait()
ca.release()
while True:
m=None
ca.acquire()
if len(mantous) != 0 :
m=mantous.pop()
else:
print("没馒头了")
cb.acquire()
cb.notify()
cb.release()
ca.wait()
ca.release()
if m is not None:
print("{0}吃{1}".format(name,m))
time.sleep(1)
class Chuofu(threading.Thread):
def __init__(self,name):
#threading.Thread.__init__(self)
super(Chuofu,self).__init__()
self.name=name
def run(self):
time.sleep(1)
while True:
ca.acquire()
for i in range(1,31):
mantous.append("第{0}个馒头".format(i))
print("做好第{0}个馒头".format(i))
time.sleep(0.1)
print("馒头做好，叫醒吃货")
ca.notify_all()
ca.release()
print("{0}去等到".format(self.name))
cb.acquire()
cb.wait()
cb.release()
class Cchihuo(threading.Thread):
def __init__(self,name):
threading.Thread.__init__(self)
self.name=name
def run(self):
ca.acquire()
ca.wait()
ca.release()
while True:
m=None
ca.acquire()
if len(mantous) != 0 :
m=mantous.pop()
else:
print("没馒头了")
cb.acquire()
cb.notify()
cb.release()
ca.wait()
ca.release()
if m is not None:
print("{0}吃{1}".format(self.name,m))
time.sleep(1)
# threading._start_new_thread(huofu,('大头和尚',))
# threading._start_new_thread(chihuo,('白眉和尚',))
# threading._start_new_thread(chihuo,('牛鼻子和尚',))
# threading._start_new_thread(chihuo,('花和尚',))
# t1=threading.Thread(target=huofu,args=('大头和尚',))
# t2=threading.Thread(target=chihuo,args=('白眉和尚',))
# t3=threading.Thread(target=chihuo,args=('牛鼻子和尚',))
# t4=threading.Thread(target=chihuo,args=('花和尚',))
# t1.start()
# t2.start()
# t3.start()
# t4.start()
Chuofu("大头和尚").start()
Cchihuo('白眉和尚').start()
Cchihuo('牛鼻子和尚').start()
Cchihuo('花和尚').start()
input() 