Understanding @RequestParam vs @PathVariable in Spring: A Comprehensive Guide

source : howtodoinjava.com

In the realm of Spring Framework, especially in Spring Web applications, two annotations play crucial roles in handling HTTP requests and mapping URL parameters to method parameters: @RequestParam and @PathVariable. While both serve similar purposes, they have distinct functionalities and are suitable for different scenarios. In this article, we'll delve deep into the nuances of these annotations, providing clear explanations and abundant code examples in Java.

What is @RequestParam?

The @RequestParam annotation in Spring MVC is used to extract query parameters from the request URL. Query parameters are typically appended to the URL after a question mark (?) and separated by ampersands (&). For example, in the URL http://example.com/api/products?id=123&name=Laptop, id and name are query parameters.

Usage of @RequestParam:

@GetMapping("/products")
public ResponseEntity<Product> getProductById(
    @RequestParam Long id,
    @RequestParam(required = false) String name
) {
    // Method logic to retrieve product details
}

In the above example, id and name are extracted from the query parameters of the request URL. The required attribute of @RequestParam can be set to false to make a…