How to use array of String as input parameters in a request for a Java application by using Spring annotations

Hello friend, today I am going to show you how to user a String[] array as an input parameter of a request. This is useful when you want to receive a series of values and then use them for any purpose.

So, let’s get started. Imagine you are creating a controller to read all pages of a CMS given the parent page, but these pages have states as integer values, so you would like to have a method that receives a list of integers (states) and then make a query to the database to get all pages that have the states in the input array.

1) In your controller class you will need to create a method -I would recommend to use Spring annotations-.

@RequestMapping(
	value = "/pages/get-by-parent/{parentUuid}", 	// The {parentUuid} is a PathVariable
	method = RequestMethod.GET, 					// This request is only valid when the request was done by GET method
	produces=MediaType.APPLICATION_JSON_VALUE)		// Result will be returned in JSON 
public ResponseEntity<List<WikiPage>> getWikiPagesList(
			@PathVariable("parentUuid") String parentUuid,	// This matches with the path variable {parentUuid}
			@RequestParam(value="includeStates[]", defaultValue="1,2,3") String[] includeStates // List of states to include
			){
	// Do something here!
}

Please, pay attention to the line, because that is the one that contains an array of String as input.

@RequestParam(value="includeStates[]", defaultValue="1,2,3") String[] includeStates // List of states to include

In this case, I am setting some default values: “1,2,3” in order to return pages with states 1, 2 or 3 in case the parameter includeStates[] is not present in the request. Of course, you can personalize this method to receive any other parameters.

I hope you find this tip useful for your development.

See you next time and remember, be happy with your code!