### Question:
CommonUtils { public static Long getNegativeLong(int number) { return ( - (long) number); } private  CommonUtils(); static ProgressDialog showLoadingDialog(Context context); static boolean isEmailValid(String email); static String getTimeStamp(); static Long getNegativeLong(int number);  }### Answer:
@Test public void getNegativeLong_NegativeInt_PositiveLong() { assertThat(CommonUtils.getNegativeLong(-2), is(2l)); }
@Test public void getNegativeLong_PositiveInt_NegativeLong() { assertThat(CommonUtils.getNegativeLong(2), is(-2l)); }