@Test
public void testCreateConnectorSkin() {

    CONNECTOR.setType(null);
    assertNull(skinFactory.createConnectorSkin(null));
    assertTrue(skinFactory.createConnectorSkin(CONNECTOR) instanceof DefaultConnectorSkin);
    CONNECTOR.setType(CONNECTOR_TYPE);
    assertTrue(skinFactory.createConnectorSkin(CONNECTOR) instanceof DefaultConnectorSkin);
    CONNECTOR.setType(CONNECTOR_TYPE);
    skinFactory.setConnectorSkin(CONNECTOR_TYPE, CustomConnectorSkin.class);
    assertTrue(skinFactory.createConnectorSkin(CONNECTOR) instanceof CustomConnectorSkin);
}