public void testAddElements() { Band band = new Band(); try { band.addElements( null ); fail( "should throw exception" ); } catch ( NullPointerException e ) { // expected } Element elem = mock( Element.class ); List<Element> elements = new ArrayList<Element>(); elements.add( elem ); band.addElements( elements ); assertEquals( 1, band.getElementCount() ); assertEquals( elem, band.getElement( 0 ) ); }