Java 并发相关的类
Executors：
factories of various implementation of Executor
Executor：
super interface, represent a consumer that receive task of Runnable,override run() to redefine how it manage Thread
ExecutorService：
subInterface of Executor , provide method to manage the running of Executor, such as isShutdown(), shutdown() ,it also provides Future<V> to monito the state of tasks.

CompletionService :
interface with logic that submit jobs to its insign Executor and then collect the result by putting Future<V> into BlockingQueue

ExecutorCompletionService:
implementation of CompletionService, all the jobs are done by its composite  Executor and it only take charge of its Completion Service logic

Future:
represent the result of an asysnchronous computation

RunnableFuture:
interface the extends Runnable and Future , it can be regarded as a task with feedback
FutureTask:
implementation of RunnableFuture

Java 并发相关的类
Executors：
factories of various implementation of Executor
Executor：
super interface, represent a consumer that receive task of Runnable,override run() to redefine how it manage Thread
ExecutorService：
subInterface of Executor , provide method to manage the running of Executor, such as isShutdown(), shutdown() ,it also provides Future<V> to monito the state of tasks.

CompletionService :
interface with logic that submit jobs to its insign Executor and then collect the result by putting Future<V> into BlockingQueue

ExecutorCompletionService:
implementation of CompletionService, all the jobs are done by its composite  Executor and it only take charge of its Completion Service logic

Future:
represent the result of an asysnchronous computation

RunnableFuture:
interface the extends Runnable and Future , it can be regarded as a task with feedback
FutureTask:
implementation of RunnableFuture