<dependency>
<groupId>org.apache.bval</groupId>
<artifactId>bval-core</artifactId>
<version>x.x.x</version>
</dependency>
public class User {
@NotNull
private String username;
}
User user = new User();
user.setUsername(null);
ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
Validator validator = factory.getValidator();
Set<ConstraintViolation<User>> violations = validator.validate(user);
for (ConstraintViolation<User> violation : violations) {
System.out.println(violation.getMessage());
}
public class User {
private String username;
}
