Access JSON Body in Spring Rest Controller - Quick Guide

When working with Spring Rest Controllers, it is common to need to access the JSON body of incoming requests. In order to do this, there are a few steps you need to take.

First, you need to ensure that the Jackson library is on your classpath. This is the library that Spring uses for JSON serialization and deserialization.

Next, you need to create a POJO that represents the structure of the JSON object you are expecting. This is known as a DTO (Data Transfer Object). You can annotate this class with the @RequestBody annotation to indicate that it should be populated from the JSON body of incoming requests.

Once you have your DTO in place, you can use it as a parameter to your Spring Rest Controller method. Spring will automatically deserialize the JSON body of the request into an instance of your DTO.

Here is an example of a Spring Rest Controller method that accesses the JSON body of an incoming request:

@PostMapping("/example")
public ResponseEntity<Void> handleExampleRequest(@RequestBody ExampleDTO exampleDTO) {
    // Do something with the exampleDTO object
    return ResponseEntity.ok().build();
}

In this example, the ExampleDTO object is populated from the JSON body of the incoming request. You can then use this object to perform whatever logic you need to in the method.

In summary, accessing the JSON body of incoming requests in a Spring Rest Controller is a simple process that requires a few setup steps. By using a DTO and the @RequestBody annotation, you can easily access the JSON data and use it in your Spring Rest Controller methods.