When should you prefer CompletableFuture and when should you avoid it?

CompletableFuture is a powerful tool in Java's concurrency framework that allows you to write non-blocking asynchronous code. However, there are scenarios where it shines and others where it may not be the best choice. Below are some considerations for when to prefer using CompletableFuture and when to avoid it.

When to Prefer CompletableFuture

• Asynchronous Programming: Use CompletableFuture when you need to perform asynchronous tasks where the result may not be immediately available.
• Chaining Tasks: When you need to carry out multiple asynchronous tasks sequentially or in parallel, CompletableFuture’s chaining capabilities (using methods like `thenApply()`, `thenAccept()`, and `thenCombine()`) are very useful.
• Error Handling: It provides fluent error handling mechanisms via methods like `exceptionally()` and `handle()`, making it easier to manage exceptions in asynchronous operations.

When to Avoid CompletableFuture

• Simple Tasks: For simple, synchronous tasks that don’t require concurrency, using CompletableFuture may add unnecessary complexity.
• Blocking Calls: If your task involves blocking calls (e.g., waiting for I/O operations), it may be better to use other concurrency mechanisms like Executors instead.
• Overhead: For very short-lived tasks where the overhead of managing the CompletableFuture is greater than the benefit, traditional threading might be more efficient.

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