@RequestParam for query strings in Spring Boot - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the @RequestParam annotation in Spring Boot?

It is used to extract query string parameters from the URL in HTTP requests and bind them to method parameters in controller methods.

beginner

How do you make a @RequestParam optional in a Spring Boot controller method?

Set the attribute 'required = false' in the @RequestParam annotation. For example: @RequestParam(required = false) String name.

intermediate

What happens if a required @RequestParam is missing in the HTTP request?

Spring Boot throws a MissingServletRequestParameterException, resulting in a 400 Bad Request response by default.

beginner

How can you provide a default value for a @RequestParam in Spring Boot?

Use the 'defaultValue' attribute in the annotation. For example: @RequestParam(defaultValue = "guest") String user.

beginner

Show a simple example of a Spring Boot controller method using @RequestParam to get a 'page' query parameter.

@GetMapping("/items") public String getItems(@RequestParam int page) { return "Page number: " + page; }

What does @RequestParam do in a Spring Boot controller?

A Binds query string parameters to method arguments

B Maps HTTP POST body to an object

C Defines a REST endpoint URL

D Handles exceptions globally

The @RequestParam annotation binds query string parameters from the URL to method parameters.

How do you make a @RequestParam optional?

A Set required = true

B Use @OptionalParam annotation

C Use @Nullable annotation

D Set required = false

Setting required = false makes the @RequestParam optional.

What is the default behavior if a required @RequestParam is missing?

A Spring Boot uses null value

B Spring Boot uses defaultValue automatically

C Spring Boot throws an error and returns 400 Bad Request

D Spring Boot ignores the parameter

If a required @RequestParam is missing, Spring Boot throws an exception and returns 400 Bad Request.

How to provide a default value for a @RequestParam?

A Use defaultValue attribute

B Use @Default annotation

C Set required = false only

D Use @Value annotation

The defaultValue attribute sets a default value if the parameter is missing.

Which HTTP method is commonly used with @RequestParam?

A POST

B GET

C PUT

D DELETE

@RequestParam is often used with GET requests to read query parameters.

Explain how @RequestParam works in Spring Boot and how to handle optional query parameters.

Think about how URLs pass data and how controller methods receive it.

Describe what happens when a required @RequestParam is missing in a request and how to avoid errors.

Consider error handling and parameter defaults.