### Question:
MongoDbGroupConverter implements HydratingModelConverter<Group, MongoDbGroup> { @Override public void hydrate(MongoDbGroup dehydrated) { }  @Override void hydrate(MongoDbGroup dehydrated); @Override Class<Group> getSourceType(); @Override MongoDbGroup convert(Group source);  }### Answer:
@Test public void hydrate_valid(){ MongoDbGroup category = new MongoDbGroup(); converter.hydrate(category); }
@Test public void hydrate_null(){ converter.hydrate(null); }