### Question:
SwitchIdConverter implements AttributeConverter<SwitchId, String> { @Override public String toGraphProperty(SwitchId value) { if (value == null) { return null; } return value.toString(); }  @Override String toGraphProperty(SwitchId value); @Override SwitchId toEntityAttribute(String value); static final SwitchIdConverter INSTANCE; }### Answer:
@Test public void shouldConvertIdToString() { SwitchId switchId = new SwitchId((long) 0x123); String graphObject = SwitchIdConverter.INSTANCE.toGraphProperty(switchId); assertEquals(switchId.toString(), graphObject); }