Why is the use of ExecutorService necessary when processing a large number of tasks?

ExecutorService in Java is used for managing a thread pool and simplifying the parallel execution of a large number of tasks. Its necessity is driven by the following reasons:

• Resource management: Instead of creating a new thread for each task, ExecutorService reuses a limited number of threads, reducing overhead.
• Simplification of code: Allows running tasks asynchronously without direct thread management.
• Execution control: Tasks can be easily canceled, waited upon for completion, and results can be obtained via Future.

Example of usage:

ExecutorService executor = Executors.newFixedThreadPool(5);
for (int i = 0; i < 10; i++) {
    int taskId = i;
    executor.submit(() -> {
        System.out.println("Task " + taskId + " is running");
    });
}
executor.shutdown();