What is the difference between using a thread pool and creating and storing individual threads in an array?

Using a thread pool differs from creating and storing individual threads in an array in several key ways:

• Resource management: A thread pool limits the number of threads running simultaneously, preventing excessive consumption of system resources. Manually creating threads and storing them in an array can easily lead to too many threads, which can reduce performance and cause failures.

• Reusing threads: In a thread pool, threads are created once and reused for different tasks, reducing the overhead of creating and destroying threads. When storing threads in an array, each thread is usually created for a specific task and can be destroyed after completion.

• Management convenience: Thread pools provide convenient APIs for scheduling and managing tasks, including task queues, timeouts, and exception handling.

Example of creating a thread pool in Java:

ExecutorService executor = Executors.newFixedThreadPool(5);
executor.submit(() -> {
    // task code
});
executor.shutdown();

In contrast, when creating threads manually:

Thread[] threads = new Thread[5];
for (int i = 0; i < 5; i++) {
    threads[i] = new Thread(() -> {
        // task code
    });
    threads[i].start();
}