Thread pool is a core concept in multithreaded programming that serves a collection of idle threads that can be used to execute a task. A thread pool can reuse previously created threads to execute the current task so that the thread is already available when the request arrives, which can reduce the time of thread creation and improve the performance of the application. Normally, thread pool can be used in a web server to handle client requests and also to maintain open connections to the database.

We can configure the maximum number of concurrent threads in the pool, which is useful for preventing overload. If all threads are busy executing a task, then a new task is placed in a queue and waits for a thread to become available.

The Java concurrency API supports the following types of thread pools:

• Fixed-thread pool: A thread pool...