源码版本 java version "11.0.8" 2020-07-14 LTS
纵览并发包 java.util.concurrent，为了方便学习暂时将包下内容分为几部分
atomic 包： 存放与原子操作相关的17个类
将其根据第一印象分类：
| 分类类型 | 类（接口） | 备注 |
|---|---|---|
| 数据 | AtomicBoolean AtomicInteger AtomicIntegerArray AtomicLong AtomicLongArray AtomicReference AtomicReferenceArray | 7 classes |
| 工具 | AtomicIntegerFieldUpdater AtomicLongFieldUpdater AtomicReferenceFieldUpdater AtomicMarkableReference AtomicStampedReference DoubleAccumulator DoubleAdder LongAccumulator LongAdder Striped64 | 10 classes |
locks 包： 存放锁相关的10个接口和类（3个接口，7个类）
| 分类类型 | 类（接口） | 备注 |
|---|---|---|
| 同步器 | AbstractOwnableSynchronizer AbstractQueuedLongSynchronizer AbstractQueuedSynchronizer (I)Condition | 1 interface 3 classes |
| 锁 | (I)Lock LockSupport (I)ReadWriteLock ReentrantLock ReentrantReadWriteLock StampedLock | 2 interfaces 4 classes |
其余61个接口和类（18个接口， 43个类）
将其按照第一印象分类：
| 分类类型 | 类（接口） | 备注 |
|---|---|---|
| 异常 (6) | BrokerBarrierException CancellationException CompletionException ExecutionException RejectedExecutionException TimeoutException | 6 classes |
| 队列 (12) | ArrayBlockingQueue (I)BlockingDeque (I)BlockingQueue ConcurrentLinkedDeque ConcurrentLinkedQueue DelayQueue LinkedBlockingDeque LinkedBlockingQueue LinkedTransferQueue PriorityBlockingQueue SynchronousQueue (I)TransferQueue | 3 interfaces 9 classes |
| 集合 (7) | ConcurrentHashMap (I)ConcurrentMap (I)ConcurrentNavigableMap ConcurrentSkipListMap ConcurrentSkipListSet CopyOnWriteArrayList CopyOnWriteArraySet | 2 interfaces 5 classes |
| 线程相关 (27) | AbstractExecutorService (I)Callable CompletableFuture (I)CompletionService (I)CompletionStage CountedCompleter (I)Delayed (I)Executor ExecutorCompletionService Executors (I)ExecutorService Flow ForkJoinPool ForkJoinTask ForkJoinWorkerThread (I)Future FutureTask RecursiveAction RecursiveTask (I)RunnableFuture (I)RunnableScheduledFuture (I)ScheduledExecutorService (I)ScheduledFuture ScheduledThreadPoolExecutor SubmissionPublisher (I)ThreadFactory ThreadPoolExecutor | 12 interfaces 15 classes |
| 线程工具 (6) | CountDownLatch CyclicBarrier Exchanger Phaser Semaphore ThreadLocalRandom | 6 classes |
| 其它 (3) | Helpers (I)RejectedExecutionHandler TimeUnit | 1 interfaces 2 classes |
梳理出基础：队列、集合 重点难点：线程相关、线程工具
