This is a final, third part of Spring MVC REST tutorial with CNVR. Here I will demonstrate how all that stuff works, which I have developed within first two parts. Here will be four sections for each type of CRUD operations: CREATE, READ, UPDATE, DELETE. As a pre-requirement you need to install any REST client for a working with a REST requests.

Spring REST: CREATE

The first operation will be creation of a smartphone. I’m going to use POSTMAN REST client. It’s a Google Chrome extension and you can download it absolutely free. When I perform CREATE or UPDATE operation I have to pass some data in a body of the request which will be used for creation or update of entity. So let’s see how it works:

👁 Spring-REST-Create

On the image above you can see completed CREATE operation. Let’s consider the most essential parts of it.

• The URL contains .json sufix
• POST selected as a HTTP method
• Request body it is the JSON document which contain required fields for a smartphone creation
• Response body it is the JSON document which in our case equals to Request body

I hope you noticed one more important detail. I talk about the Content-type = application/json. As you remember in the methods of controoler I specified such parameters as “consumes“:

...
	@RequestMapping(value="/create", method=RequestMethod.POST, 
			produces = "application/json", consumes = "application/json")
	@ResponseBody
	public Smartphone createSmartphone(@RequestBody Smartphone smartphone) {
		return smartphoneService.create(smartphone);
	}
...

That’s mean that the method will work just with JSON. Spring permits to set multiple types for “produces” and “consumes” attributes.

Spring REST: READ

The second operation will show how to select some records.

👁 Spring-REST-Read

In this case I just used the HTTP GET request and it returned to me a list of existing smartphones in JSON format.

Spring REST: UPDATE

A HTTP PUT request as a HTTP POST request should have body content to be have information about updating data.

👁 Spring-REST-Update

Spring REST: DELETE

In the most straightforward case HTTP DELETE request just need to know ID of entity which will be removed.

👁 Spring-REST-Delete

As you see everything goes as in previous examples except HTTP request type, which was changed to DELETE.

It’s not all

But as you remember I have developed some methods in the controller which return ModelAndView object. Hence you can do the same operations through a web interface. It was very challenging for me to write these tutorials. I covered here just a top of the “REST” iceberg. In the future I will write some articles about AJAX, exception handling and other cool stuff related to the REST.