How to implement asynchronous task execution in Java?

In Java (including on Android), there are several approaches to perform asynchronous tasks:

1. Thread / Runnable: Create a new thread to execute a task.

2. ExecutorService: Managed thread pool for executing tasks.

3. AsyncTask (deprecated in Android): Allowed executing tasks in the background with UI updates.

4. CompletableFuture (Java 8+): Enables writing asynchronous code with chains of actions.

5. RxJava: A library for reactive programming with support for asynchrony.

6. Coroutines (Kotlin): A modern way of asynchronous programming on Android.

Example using ExecutorService:

ExecutorService executor = Executors.newSingleThreadExecutor();
executor.submit(() -> {
    // Long operation
    System.out.println("Executing in background");
    // After execution, UI can be updated via Handler or runOnUiThread
});
executor.shutdown();

This method allows executing tasks in a separate thread without blocking the main application thread.