How to validade objects on backend - Spring Boot

What problem does this solve

If you need to validate objects on backend with Spring boot. You can create validation to each property with custom messages. A very useful feature to your projects.

 

 

 

 

Prerequisites

1.     Model Class
2.     Controller Class
3.     End Point with @RequestBody 

The solution

    Add the starter-validation dependency on your pom.xml

 

<dependency>

    <groupId>org.springframework.boot</groupId>

<artifactId>spring-boot-starter-validation</artifactId>

</dependency>

 

     On your Model add the annotations for validation on each property. You can see more annotations in javax validation constraints java doc.

import javax.validation.constraints.Email;

import javax.validation.constraints.NotBlank;

@Data

@AllArgsConstructor

@NoArgsConstructor

public class UserLoginDTO {

@Email

private String email;

@NotBlank

private String password;

}

  On the endpoint add @Valid Annotation after @RequestBody

@PostMapping("/login")

public ResponseEntity<User> login(@RequestBody @Valid UserLoginDTO loginDTO) {

var loggedUser = service.doLogin(loginDTO.getEmail(), loginDTO.getPassword());

return ResponseEntity.ok(loggedUser);

}

That's It.

 Thanks for reading!