SimplePOJOWithStringId pojoWithStringId = new SimplePOJOWithStringId();
pojoWithStringId.setId("abcd1234");
ObjectToDocumentConverter<SimplePOJOWithStringId>
converter = MonjoConverterFactory.getInstance()
.configure(new DefaultNamingStrategy())
.getDefaultObjectConverter(SimplePOJOWithStringId.class);
DBObject document = converter.from(pojoWithStringId).toDocument();
assertThat(document.containsField("_id"), is(true));