Java Handler Pattern: Pros & Cons

Advantages:

1. Strong decoupling: The Handler pattern decouples the sender of the request from the receiver, so the sender doesn’t need to know how the request is being handled.
2. Strong scalability: it is easy to add new specific handlers to deal with new types of requests without modifying the existing code.
3. Simplify the code logic by breaking down complex processing into multiple Handlers, each responsible for handling its own part, making the code more clear.

Drawbacks:

1. Having too many handlers can lead to a decrease in performance: If requests need to go through multiple handlers for processing, it may result in a performance loss.
2. Chain call may be caused: If there is a dependency between Handlers, chain call situation may occur, which is difficult to maintain.
3. Complex interactions between Handlers may lead to increased code complexity and make it more difficult to comprehend.