@Entity
public class MdMaterialMinimal {

    @Id
    private String materialNumber;

    private String materialName;

    MdMaterialMinimal() {
        super();
    }

    public MdMaterialMinimal(String materialNumber, String materialName) {
        super();
        this.materialNumber = materialNumber;
        this.materialName = materialName;
    }
}

Session session = entityManager.unwrap(Session.class);
            MdMaterialMinimal exampleEntity = new MdMaterialMinimal("4711", null);

            Example example = Example.create(exampleEntity);

            Criteria criteria = session.createCriteria(MdMaterialMinimal.class).add(example);
            System.out.println(criteria.uniqueResult());

Hibernate: /* criteria query */ select this_.materialNumber as material1_5_0_, this_.materialName as material2_5_0_ from MdMaterialMinimal this_ where (1=1)