import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
/**
* 利用线程池创建线程
*
* 线程池相关API：ExecutorService、Executors
* > ExecutorService：
* - 常见子类：ThreadPoolExecutor
* - 常见方法：
* ~ void execute(Runnable command)：执行任务，只用来执行Runnable
* ~ <T>Future<T> submit(Callable<T> task)：执行任务，一般用来执行Callable
* ~ void shutdown()：关闭线程连接池
* > Executors：
* - 用于创建并返回不同类型的线程池
* - 常见方法：
* ~ Executors.newCachedThreadPool()：创建一个可根据需要创建新线程的线程池
* ~ Executors.newFixedThreadPool(n)：创建一个可重用固定线程数的线程池
* ~ Executors.newSingleThreadExecutor()：创建一个只有一个线程的线程池
* ~ Executors.newScheduledThreadPool(n)：创建一个线程池，可以定期地执行命令
*
* @create 2022-01-21 10:02
*/
class NumIncrease_Runnable implements Runnable {
@Override
public void run() {
for (int i = 1; i <= 10; i++) {
System.out.println(Thread.currentThread().getName() + " " + i);
}
}
}
class NumIncrease_Callable implements Callable{
private int sum = 0;
@Override
public Object call() throws Exception {
for (int i = 11; i <= 20; i++) {
System.out.println(Thread.currentThread().getName() + " " + i);
sum += i;
}
return sum;
}
}
public class ThreadTest_4 {
public static void main(String[] args) {
ExecutorService executorService = Executors.newFixedThreadPool(10);
NumIncrease_Runnable runnable = new NumIncrease_Runnable();
NumIncrease_Callable callable = new NumIncrease_Callable();
executorService.execute(runnable); //只用于Runnable
executorService.submit(callable); //一般用于Callable
executorService.shutdown(); //关闭线程池
}
}
其中一个执行过程：
pool-1-thread-2 11
pool-1-thread-2 12
pool-1-thread-1 1
pool-1-thread-2 13
pool-1-thread-1 2
pool-1-thread-2 14
pool-1-thread-1 3
pool-1-thread-2 15
pool-1-thread-1 4
pool-1-thread-2 16
pool-1-thread-1 5
pool-1-thread-2 17
pool-1-thread-1 6
pool-1-thread-2 18
pool-1-thread-1 7
pool-1-thread-2 19
pool-1-thread-2 20
pool-1-thread-1 8
pool-1-thread-1 9
pool-1-thread-1 10
Process finished with exit code 0
