Integers { public static Integer parse(final String s) { try { return Integer.parseInt(s); } catch (final NumberFormatException e) { return null; } } private  Integers(); static Integer parse(final String s);  }
@Test public void testParse() { final String nullString = null; final String emptyString = null; final String integerString = "1"; final String decimalString = "1.0"; assertThat(Integers.parse(nullString), is(nullValue())); assertThat(Integers.parse(emptyString), is(nullValue())); assertThat(Integers.parse(integerString), is(1)); assertThat(Integers.parse(decimalString), is(nullValue())); }