Java Programming for Complete Beginners - Java 16 - Step 11 - Executor Service - Returning a Future from Thread Using Ca

The video tutorial explains how to use an executor service to execute tasks in Java, focusing on returning values from threads using the Callable interface. It covers creating a callable task, implementing the Callable interface, and executing tasks with an executor service. The tutorial also discusses handling results with Future and managing exceptions, providing a comprehensive guide to managing concurrent tasks in Java.

What is the primary purpose of using a callable task in an executor service?

• To manage multiple threads simultaneously

• To execute tasks that return a value

• To improve the speed of task execution

• To execute tasks without returning any value

Which interface must be implemented to create a task that returns a value?

• Thread

• Runnable

• Callable

• Executor

What method is used to execute a callable task in an executor service?

• execute()

• submit()

• start()

• run()

What is the role of the Future object when working with callable tasks?

• It manages the thread pool size

• It holds the result of the callable task

• It logs the task's execution details

• It stores the task's execution time

How does the get() method of a Future object behave?

• It immediately returns the result

• It waits for the task to complete and then returns the result

• It throws an exception if the task is not completed

• It cancels the task execution

What happens if you call get() on a Future object before the task is complete?

• It throws an exception

• It returns null

• It waits for the task to complete

• It returns a default value

Why is it important to handle exceptions when using the get() method on a Future?

• To ensure the task completes successfully

• To manage the thread pool efficiently

• To prevent the program from crashing

• To improve the task execution speed