#Spring boot rest api how to
#Spring boot rest api code

This dependency contains a dependency to the RestTemplate class. The dependency spring-boot-starter-web is a starter for building web applications.

We have added the web dependency to the Maven pom.xml. To work with the examples of using RestTemplate, let us first create a Spring Boot project with the help of the Spring boot Initializr, and then open the project in our favorite IDE.

#Spring boot rest api how to

We will see how to use the above methods of RestTemplate with the help of some examples in subsequent sections. PostForLocation(): creates a new resource using the HTTP POST method and returns the location of the newly created resource.įor additional information on the methods of RestTemplate, please refer to the Javadoc. PostForObject() : creates a new resource using HTTP POST method and returns an entity. Put(): updates a resource for a given URL using the HTTP PUT method. OptionsForAllow(): executes an OPTIONS request and uses the Allow header to return the HTTP methods that are allowed under the specified URL.ĭelete(): deletes the resources at the given URL using the HTTP DELETE method. HeadForHeaders(): executes a HEAD request and returns all HTTP headers for the specified URL.

#Spring boot rest api code

GetForObject() : similar to getForEntity(), but returns the resource directly.Įxchange(): executes a specified HTTP method, such as GET, POST, PUT, etc, and returns a ResponseEntity containing both the HTTP status code and the resource as an object.Įxecute() : similar to the exchange() method, but takes additional parameters: RequestCallback and ResultSetExtractor. GetForEntity(): executes a GET request and returns an object of ResponseEntity class that contains both the status code and the resource as an object.

the second part in the name indicates returned element.įor example, the method getForObject() will perform a GET and return an object.

the first part in the name indicates the HTTP method being invoked.

The names of most of the methods are based on a naming convention: RestTemplate provides higher-level methods for each of the HTTP methods which make it easy to invoke RESTful services. Some Useful Methods of RestTemplateīefore looking at the examples, it will be helpful to take a look at the important methods of the RestTemplate class. However, we can switch to another HTTP client library which we will see in a later section. The HTTP client library takes care of all the low-level details of communication over HTTP while the RestTemplate adds the capability of transforming the request and response in JSON or XML to Java objects.īy default, RestTemplate uses the class as the HTTP client. It is a higher-order API since it performs HTTP requests by using an HTTP client library like the JDK HttpURLConnection, Apache HttpClient, and others. This article is accompanied by a working code example on GitHub.Īccording to the official documentation, RestTemplate is a synchronous client to perform HTTP requests. In this tutorial, we will understand how to use RestTemplate for invoking REST APIs of different shapes. RestTemplate is a class within the Spring framework that helps us to do just that. Hence for applications to function gracefully, they need to consume APIs elegantly and consistently. Many applications need to invoke REST APIs for some or all of their functions.