java线程知识总结

public class Test {
public static void main(String[] args) {
Thread t1 = new MyThread1();
t1.start();

for (int i = 0; i < 20; i++) {
System.out.println("主线程第" + i + "次执行！");
if (i > 2) try {
//t1线程合并到主线程中，主线程停止执行过程，转而执行t1线程，直到t1执行完毕后继续。
t1.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}

class MyThread1 extends Thread {
public void run() {
for (int i = 0; i < 10; i++) {
System.out.println("线程1第" + i + "次执行！");
}
}
}

public class Test {
public static void main(String[] args) {
Thread t1 = new MyThread1();
Thread t2 = new Thread(new MyRunnable());

t2.start();
t1.start();
}
}

class MyThread1 extends Thread {
public void run() {
for (int i = 0; i < 10; i++) {
System.out.println("线程1第" + i + "次执行！");
}
}
}

class MyRunnable implements Runnable {
public void run() {
for (int i = 0; i < 10; i++) {
System.out.println("线程2第" + i + "次执行！");
Thread.yield();
}
}
}

public class ThreadA {
public static void main(String[] args) {
ThreadB b = new ThreadB();
//启动计算线程
b.start();
//线程A拥有b对象上的锁。线程为了调用wait()或notify()方法，该线程必须是那个对象锁的拥有者
synchronized (b) {
try {
System.out.println("等待对象b完成计算。。。");
//当前线程A等待
b.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("b对象计算的总和是：" + b.total);
}
}
}

public class ThreadB extends Thread {
int total;

public void run() {
synchronized (this) {
for (int i = 0; i < 101; i++) {
total += i;
}
//（完成计算了）唤醒在此对象监视器上等待的单个线程，在本例中线程A被唤醒
notify();
}
}
}

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
* Java线程：锁
*
* @author leizhimin 2009-11-5 10:57:29
*/
public class Test {
public static void main(String[] args) {
//创建并发访问的账户
MyCount myCount = new MyCount("95599200901215522", 10000);
//创建一个锁对象
Lock lock = new ReentrantLock();
//创建一个线程池
ExecutorService pool = Executors.newCachedThreadPool();
//创建一些并发访问用户，一个信用卡，存的存，取的取，好热闹啊
User u1 = new User("张三", myCount, -4000, lock);
User u2 = new User("张三他爹", myCount, 6000, lock);
User u3 = new User("张三他弟", myCount, -8000, lock);
User u4 = new User("张三", myCount, 800, lock);
//在线程池中执行各个用户的操作
pool.execute(u1);
pool.execute(u2);
pool.execute(u3);
pool.execute(u4);
//关闭线程池
pool.shutdown();
}
}

/**
* 信用卡的用户
*/
class User implements Runnable {
private String name;                //用户名
private MyCount myCount;        //所要操作的账户
private int iocash;                 //操作的金额，当然有正负之分了
private Lock myLock;                //执行操作所需的锁对象

User(String name, MyCount myCount, int iocash, Lock myLock) {
this.name = name;
this.myCount = myCount;
this.iocash = iocash;
this.myLock = myLock;
}

public void run() {
//获取锁
myLock.lock();
//执行现金业务
System.out.println(name + "正在操作" + myCount + "账户，金额为" + iocash + "，当前金额为" + myCount.getCash());
myCount.setCash(myCount.getCash() + iocash);
System.out.println(name + "操作" + myCount + "账户成功，金额为" + iocash + "，当前金额为" + myCount.getCash());
//释放锁，否则别的线程没有机会执行了
myLock.unlock();
}
}

/**
* 信用卡账户，可随意透支
*/
class MyCount {
private String oid;         //账号
private int cash;             //账户余额

MyCount(String oid, int cash) {
this.oid = oid;
this.cash = cash;
}

public String getOid() {
return oid;
}

public void setOid(String oid) {
this.oid = oid;
}

public int getCash() {
return cash;
}

public void setCash(int cash) {
this.cash = cash;
}

@Override
public String toString() {
return "MyCount{" +
"oid='" + oid + '\'' +
", cash=" + cash +
'}';
}
}