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