ExecutorService

ExecutorService is an interface which allows us to execute tasks on thread asynchronously

Instantiation using Executors Factory class

Instance can be retrieved from Executors factory class using different factory methods based on the number and types of threads needed.

For single thread

ExecutorService es = Executors.newSingleThreadExecutor();  

For thread pool

ExecutorService es = Executors.newFixedThreadPool(10); 

For scheduled thread pool

In scheduled thread pool, we can schedule tasks of the threads.

ExecutorService es = Executors.newScheduledThreadPool(10); 

Methods

Executing Threads

//We can use the following methods
execute(Runnable task)
submit(Runnable task) / submit(Callable<T> task)
invokeAny(Collection<? extends Callable<T>> tasks)
invokeAll(Collection<? extends Callable<T>> tasks);

Shutting down

We can use the following methods after we're done. If we don't, the threads will keep running and JVM won't shut down.

• shutdown() method
• shutdownNow() method
• awaitTermination() method

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Backlinks

• Multithreading (cs)
• Multithreading (cs)