How can I handle exceptions in Java's CompletableFuture?

How can I handle exceptions in Java's CompletableFuture?

You can handle exceptions in CompletableFuture using methods like exceptionally(), handle(), or whenComplete(). Would you like an example?

Yes, please provide an example using exceptionally().

Sure! Here's a simple example:

CompletableFuture.supplyAsync(() -> {
    // Simulate a task that may throw an exception
    if (true) throw new RuntimeException("Error occurred!");
    return "Success!";
})
.exceptionally(ex -> {
    System.out.println(ex.getMessage());
    return "Fallback value";
});

This will catch the exception and return a fallback value.

What if I want to log the exception instead of returning a fallback value?

You can log the exception in the exceptionally() method like this:

.exceptionally(ex -> {
    System.err.println("Exception: " + ex.getMessage());
    return null; // or any other value
});

This way, you can handle the exception and still control the return value.