AtomicProperties { public double getNormalizedMass(String symbol) { return this.getMass(symbol) / this.getMass("C"); } private  AtomicProperties(); double getVdWVolume(String symbol); double getNormalizedVdWVolume(String symbol); double getElectronegativity(String symbol); double getNormalizedElectronegativity(String symbol); double getPolarizability(String symbol); double getNormalizedPolarizability(String symbol); double getMass(String symbol); double getNormalizedMass(String symbol); static AtomicProperties getInstance();  }
@Test public void testGetNormalizedMass() throws Exception { AtomicProperties props = AtomicProperties.getInstance(); double mass = props.getNormalizedMass("C"); Assert.assertTrue(mass > 0); }