Slaying Errors with Style: Exception Handling in Spring Boot’s RESTful Realm

Mastering Exception Handling with Spring Boot’s RESTful Magic

Exceptions and exception handlers play a crucial role in software development by allowing developers to manage errors and unexpected behaviors in a controlled and organized manner. They help to separate error handling logic from the main application code, making it easier to maintain and debug.

This article provides you a elegant and practical way to combine exception handling and RESTful API without without so many if & else in application layer.

Let’s start with the basic structure of exception handling in Spring Boot.

Custom Exception

Create a custom exception class that extends the `RuntimeException` class.

Usage

Use the custom exception in your code by throwing it when needed.

Exception Handler

Create a global exception handler using @ControllerAdvice and @ExceptionHandler annotations to handle exception.

We use BAD_REQUEST(400) HTTP status code for invalid of the request in this example. You can also easily use NOT_FOUND(404) to handle ZERO record of the query result to get rid of redundant source code in application layer to handle this condition.

Error Response for the Front-end

Create a custom error response class to hold the error details.

※The error details depend on the your needs of Front-end.

Now, when a CustomException is thrown, the global exception handler will catch it and return an appropriate response with the custom error details. :)

In summary, exceptions and exception handlers are essential tools for handling errors and unexpected behaviors in a clean, organized, and user-friendly manner. They help to improve the overall stability, maintainability, and user experience of your applications. We can apply exceptions and exception handlers in an elegant way to handle different conditions of our application without brunch of redundant source codes.