@Test
public void testJoin()
{

    DataElement deA = new DataElement( "DataElementA" );
    DataElement deB = new DataElement( "DataElementB" );
    DataElement deC = new DataElement( "DataElementC" );
    List<DataElement> elements = Lists.newArrayList( deA, deB, deC );
    String actual = ObjectUtils.join( elements, ", ", de -> de.getName() );
    assertEquals( "DataElementA, DataElementB, DataElementC", actual );
    assertEquals( null, ObjectUtils.join( null, ", ", null ) );
}