How can I implement validation in a Spring Boot application?

How can I implement validation in a Spring Boot application?

You can use the @Valid annotation along with JSR-303/JSR-380 annotations like @NotNull, @Size, etc. on your model classes.

Can you show me an example of a model class with validation annotations?

Sure! Here's a simple example:

import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;

public class User {
    @NotNull
    private Long id;

    @NotNull
    @Size(min = 2, max = 30)
    private String name;

    // Getters and Setters
}

How do I handle validation errors in my controller?

You can use @ExceptionHandler to catch MethodArgumentNotValidException and return a custom response.

What dependencies do I need to include for validation?

You need to include spring-boot-starter-validation in your pom.xml or build.gradle file.