@Test
public void testGetOpenFuturePeriods()
{

    DataElement deA = new DataElement( "A" );
    assertEquals( 0, deA.getOpenFuturePeriods() );
    DataSet dsA = new DataSet( "A" );
    DataSet dsB = new DataSet( "B" );
    dsA.setOpenFuturePeriods( 0 );
    dsB.setOpenFuturePeriods( 3 );
    dsA.addDataSetElement( deA );
    assertEquals( 0, deA.getOpenFuturePeriods() );
    dsB.addDataSetElement( deA );
    assertEquals( 3, deA.getOpenFuturePeriods() );
}