When to go for @RequestParam and @PathVariable

Question

Just curious to know in which scenario we should go for @RequestParam and @PathVariable. I know that:

1. @RequestParam takes parameter value whereas @PathVariable takes placeholder value
2. @RequestParam can be optional (required=false) while making request whereas @PathVariable value has to be provided.
3. When we want to use @RequestParam we have to know the property syntax but for @PathVariable not required

Is there any other reason to go for specific one?

Answer 1

• org.springframework.web.bind.annotation.RequestParam is used to bind Query String.
• org.springframework.web.bind.annotation.PathVariable is used to bind URL path.
• org.springframework.web.bind.annotation.RequestBody is used to bind HTTP Body.
• org.springframework.http.RequestEntity will give you some added flexibility in defining arbitrary HTTP Entity headers along with HTTP Body.

Best Practice:

• If you want to identify a resource, you should use Path Variable.
• But if you want to sort or filter items, then you should use query parameter.

Example:

 /users # Fetch a list of users
/users?occupation=programmer # Fetch a list of user with filter programmer
/users/123 # Fetch a user who has id 123

you can get side effects. You don’t have to define other URL and other query parameter to achieve basic CRUD functions.You change HTTP method depends on what you want to do.

/users [GET] # Fetch a list of users
/users [POST] # Create new user
/users/123 [PUT] # Update user
/users/123 [DELETE] # remove user

Putting optional parameters in the Template URL will end up getting really messy, So I would recommend to put optional parameter in Query String.

Answer 2

Use @PathVariable if you want to adhere to 'statefull' URLs.

For Example:-

/customer/:id   Customer view/edit page
/customer/      Customer Add page
/customer/list  List Customer Page
/customer/:cid/order  All order of a Customer
/customer/:cid/order/:oid  Specific order of a partucular Customer.

Wisely using Path Variable will result in URL that gives you hint/clue about what the resulting view/page means.

This also lets you support refresh,back & forward operation with no extra effort.

@RequestParams can be used to exatract data which is not passed as path params. Your MVC handler can have combination of two as required.