What's thread in Java?

Lifecycle of a thread in Java

Life cycle of a thread in Java

Lifecycle and States of a Thread in Java

How?

Thread()

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public class CreateThreadByThreadClass extends Thread {
@Override
public void run() {
int loopTimes = 100;
for (int i = 0; i < loopTimes; i++) {
System.out.println(Thread.currentThread().getName() + " " + i);
}
}
}

Runnable()

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public class CreateThreadByRunnableInterface implements Runnable {
@Override
public void run() {
int loopTimes = 100;
for (int i = 0; i < loopTimes; i++) {
System.out.println(Thread.currentThread().getName() + " " + i);
}
}
}

Callable()

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public class CreateThreadByCallableInterface implements Callable<Integer> {
@Override
public Integer call() {
int sum = 0, loopTimes = 100;
for (int i = 0; i < loopTimes; i++) {
System.out.println(Thread.currentThread().getName() + " " + i);
sum += i;
}
return sum;
}
}

Tester

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public class Tester {


/**
* 创建线程池
*/
private static final ThreadFactory threadFactory = new ThreadFactoryBuilder().setNameFormat("pool-%d").build();
private static final ExecutorService executorService = new ThreadPoolExecutor(5, 200, 0L,
TimeUnit.MILLISECONDS, new LinkedBlockingQueue<>(1024), threadFactory, new ThreadPoolExecutor.AbortPolicy());

public static void main(String[] args) {
int loopTimes = 100;
//testThread(loopTimes);
testRunnable(loopTimes);
//testCallable(loopTimes);
}

private static void testRunnable(int loopTimes) {
for (int i = 0; i < loopTimes; i++) {
System.out.println(Thread.currentThread().getName() + " " + i);
if (i == 30) {
CreateThreadByRunnableInterface myRunnable = new CreateThreadByRunnableInterface();
// 不要显示创建线程,通过线程池创建
executorService.execute(myRunnable);
executorService.execute(myRunnable);
executorService.shutdown();
}
}
}

private static void testThread(int loopTimes) {
for (int i = 0; i < loopTimes; i++) {
System.out.println(Thread.currentThread().getName() + " " + i);
if (i == 30) {
Thread thread1 = new CreateThreadByThreadClass();
Thread thread2 = new CreateThreadByThreadClass();
thread1.start();
thread2.start();
}
}
}

private static void testCallable(int loopTimes) {
for (int i = 0; i < loopTimes; i++) {
System.out.println(Thread.currentThread().getName() + " " + i);
if (i == 30) {
Callable<Integer> myCallable = new CreateThreadByCallableInterface();
FutureTask<Integer> futureTask = new FutureTask<>(myCallable);
executorService.submit(futureTask);
executorService.shutdown();
}
}
}
}