### Question:
PostgreSQLHStoreType extends ImmutableType<Map> { @Override protected Map get(ResultSet rs, String[] names, SharedSessionContractImplementor session, Object owner) throws SQLException { return (Map) rs.getObject(names[0]); } PostgreSQLHStoreType(); @Override int[] sqlTypes(); static final PostgreSQLHStoreType INSTANCE; }### Answer:
@Test public void test() { doInJPA(entityManager -> { Book book = new Book(); book.setIsbn("978-9730228236"); book.getProperties().put("title", "High-Performance Java Persistence"); book.getProperties().put("author", "Vlad Mihalcea"); book.getProperties().put("publisher", "Amazon"); book.getProperties().put("price", "$44.95"); entityManager.persist(book); }); doInJPA(entityManager -> { Book book = entityManager.unwrap(Session.class) .bySimpleNaturalId(Book.class) .load("978-9730228236"); assertEquals("High-Performance Java Persistence", book.getProperties().get("title")); assertEquals("Vlad Mihalcea", book.getProperties().get("author")); }); }