@ Pure public PointGroup getGroupAt ( int index ) { final int count = getGroupCount ( ) ; if ( index < 0 ) { throw new IndexOutOfBoundsException ( index + "<0" ) ; //$NON-NLS-1$ } if ( index >= count ) { throw new IndexOutOfBoundsException ( index + ">=" + count ) ; //$NON-NLS-1$ } return new PointGroup ( index ) ; }
Replies the part at the specified index .