Learn

In the previous exercise, we discussed the use of @RequestParam to pass data from query parameters to a method. @RequestParam is perfect to use when we want to filter the results or return several resources. However, when we want to return more specific entities we can use the @PathVariable annotation.

@PathVariable maps template variables in the request URI directly to a method’s parameters. For example, we could define a template path

/books/{id}

and use the URI

localhost:4001/books/28937

to pass the path variable “28937” to a method’s id parameter. On the server side, we would have an endpoint that looks up books by ID as follows:

@GetMapping("/{id}") public Book isBookAvailable(@PathVariable int id) { return book.findByID(id); }

In the above example, use of the @PathVariable at the method parameter level allows us to take a variable received from the request URI and pass it into a method as a parameter. As a developer, this simple annotation affords us ample opportunities to process data from HTTP requests.

We’ve seen two ways to capture parameters from a request URI. @RequestParam captures the id included in the URI /books?id=28937 and @PathVariable captures the id included in the URI /books/28937 as long as the path includes the {id} variable in books/{id}.

Instructions

1.

Ingrid likes to keep track of every time one of the super heroes lends their assistance to the public. She’s developed a resource that will report help requests by postal code.

Add the @PathVariable annotation to pass values from the getHeroReportByPostal() method to the endpoint.

2.

Using curl, make a request to the endpoint with an postalCode value of 64672.

Sign up to start coding

Mini Info Outline Icon
By signing up for Codecademy, you agree to Codecademy's Terms of Service & Privacy Policy.

Or sign up using:

Already have an account?