JUnit validate JSR-303 with assertion

JSRValidationTest.java

import org.hibernate.validator.constraints.NotEmpty;
import org.junit.BeforeClass;
import org.junit.Test;

import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.Validator;
import javax.validation.ValidatorFactory;
import java.util.Set;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

public class JSRValidationTest {

    private static Validator validator;

    @BeforeClass
    public static void setUp() {
        ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
        validator = factory.getValidator();
    }

    @Test
    public void myObject_NotNull_Test() {
        MyObject myObject = new MyObject(null);
        Set<ConstraintViolation<MyObject>> violations = validator.validate(myObject);
        assertConstraint(violations, ConstraintValidationTypes.MAY_NOT_BE_EMPTY);
    }

    protected <T> void assertConstraint(Set<ConstraintViolation<T>> violations, ConstraintValidationTypes... constraintValidationTypes) {
        for (ConstraintValidationTypes validation: constraintValidationTypes) {
            String expected = validation.getMessage();
            assertTrue(String.format("Missing: %s", expected), violations.stream().anyMatch(t -> t.getMessage().equals(expected)));
        }
        assertEquals(constraintValidationTypes.length, violations.size());
    }
}

class MyObject {
    @NotEmpty
    private String value;

    public MyObject(String value) {
        this.value = value;
    }
}

enum ConstraintValidationTypes {
    MAY_NOT_BE_NULL("may not be null"),
    MAY_NOT_BE_EMPTY("may not be empty");

    private String message;

    ConstraintValidationTypes(String message) {
        this.message = message;
    }

    public String getMessage() {
        return message;
    }
}