@Test public void testNull() { Filter filter = new FilterNull(); assertFalse( invokeFilter( filter, new Tuple( 1 ) ) ); assertTrue( invokeFilter( filter, new Tuple( (Comparable) null ) ) ); assertFalse( invokeFilter( filter, new Tuple( "0", 1 ) ) ); assertTrue( invokeFilter( filter, new Tuple( "0", null ) ) ); assertTrue( invokeFilter( filter, new Tuple( null, null ) ) ); }