转自：https://www.cnblogs.com/dolphin0520/p/3932921.html
java.uitl.concurrent.ThreadPoolExecutor类是线程池中最核心的一个类。
1、public class ThreadPoolExecutor extends AbstractExecutorService
2、public abstract class AbstractExecutorService implements ExecutorService
3、public interface ExecutorService extends Executor
4、public interface Executor {
void execute(Runnable command);}