Executor: 执行对象
*** Executor: 执行已提交的Runnable任务的对象**
[* ExecutorService](https://www.itzhai.com/the-executorservice-common-method-newfixedthreadpool-of-create-fixed-size-thread-pool.html)
[ThreadPoolExecutor](https://www.itzhai.com/the-threadpoolexecutor-the-use-and-presentation-of.html) 动态的线程池
AbstractExecutorService
* ScheduleExecutorService 任务调度
ScheduledThreadPoolExecutor
Executors 工厂方法，构建4种线程池
*** CompletionService 生产新的异步任务与使用已完成任务的结果分离开来的服务**
[ExecutorCompletionService](https://www.itzhai.com/the-introduction-and-use-of-completionservice.html)
*** Future 表示异步计算的结果**
* FutureTask
* RunnableFuture
RunnableScheduledFuture
* Callable 返回结果并可能抛出异常的任务
*** RejectedExecutionHandler 无法由ThreadPoolExecutor执行的任务处理程序**
Queue: 任务队列
ConcurrentLinkQueue 基于链接节点的无界线程安全队列
*** BlockingQueue 阻塞队列**
ArrayBlockingQueue
DelayQueue
LinkedBlockingQueue
PriorityBlocingQueue
SynchronousQueue
BlockingDeque 阻塞双端队列
LinkedBlockingDeque
Concurrent Collection: 并发集合
*** ConcurrentMap**
ConcurrentHashMap
* ConcurrentNavigableMap
ConcurrentSkipListMap
ConcurrentSkipListSet 基于ConcurrentSkipListMap的可缩放并发NavigableSet
CopyOnWriteArrayList ArrayList的一个线程安全的变体
CopyOnWriteArraySet
atomic: 原子
基本变量的原子操作
lock: 锁
*** Lock**
ReentrantLock
*** ReadWriteLock**
ReenTrantReadWriteLock
*** Condition**
Timer: 计时器
TimeUnit
Synchronizer: 同步
Semaphore 计数信号量
CountDownLatch 同步辅助类，计数器
CyclicBarrier 同步辅助类，使一组线程相互等待
Exchanger 可以再对中队元素进行配对和交换的线程的同步点
