Opposite of adding milliseconds to a java date, this example shows how to subtract milliseconds from a date using java's Calendar.add, java 8 date time api, joda’s DateTime.minusMillis and apache commons DateUtils.addMilliseconds. In each of the examples below, we will set a date that represents new years day or January 1st. Then we will subtract X milliseconds to return a date that reperesents new years eve or December 31st.
Straight up Java
@Test
public void subtract_milliseconds_from_date_in_java () {
Calendar newYearsDay = Calendar.getInstance();
newYearsDay.set(2013, 0, 1, 0, 0, 0);
Calendar newYearsEve = Calendar.getInstance();
newYearsEve.setTimeInMillis(newYearsDay.getTimeInMillis());
newYearsEve.add(Calendar.MILLISECOND, -1000);
SimpleDateFormat dateFormatter = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss S z");
logger.info(dateFormatter.format(newYearsDay.getTime()));
logger.info(dateFormatter.format(newYearsEve.getTime()));
assertTrue(newYearsEve.before(newYearsDay));
}
Output
01/01/2013 00:00:00 487 CST
12/31/2012 23:59:59 487 CST
Java 8 Date and Time API
Java 8 LocalDateTime.minus will return a copy of the LocalDateTime with the specified amount subtracted, in this case ChronoField.MILLI_OF_DAY.
@Test
public void subtract_milliseconds_from_date_in_java8() {
LocalDateTime newYearsDay = LocalDateTime.of(2013, Month.JANUARY, 1, 0,
0, 0, 0);
LocalDateTime newYearsEve = newYearsDay.minus(1,
ChronoField.MILLI_OF_DAY.getBaseUnit());
java.time.format.DateTimeFormatter formatter = java.time.format.DateTimeFormatter
.ofPattern("MM/dd/yyyy HH:mm:ss S");
logger.info(newYearsDay.format(formatter));
logger.info(newYearsEve.format(formatter));
assertTrue(newYearsEve.isBefore(newYearsDay));
}
Output
01/01/2013 00:00:00 0
12/31/2012 23:59:59 9
Joda Time
Joda DateTime.minusMillis will return a copy the DateTime minus the specified number of milliseconds.
@Test
public void subtract_milliseconds_from_date_in_java_with_joda () {
DateTime newYearsDay = new DateTime(2013, 1, 1, 0, 0, 0, 0);
DateTime newYearsEve = newYearsDay.minusMillis(60);
DateTimeFormatter fmt = DateTimeFormat.forPattern("MM/dd/yyyy HH:mm:ss S z");
logger.info(newYearsDay.toString(fmt));
logger.info(newYearsEve.toString(fmt));
assertTrue(newYearsEve.isBefore(newYearsDay));
}
Output
01/01/2013 00:00:00 0 CST
12/31/2012 23:59:59 9 CST
Apache Commons
Apache commons DateUtils.addMilliseconds will adds a number of milliseconds, in this case a negative number of milliseconds, to the date returning a new object.
@Test
public void subtract_milliseconds_from_date_in_java_apachecommons () {
Calendar newYearsDay = Calendar.getInstance();
newYearsDay.set(2013, 0, 1, 0, 0, 0);
Date newYearsEve = DateUtils.addMilliseconds(newYearsDay.getTime(), -1000);
SimpleDateFormat dateFormatter = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss z");
logger.info(dateFormatter.format(newYearsDay.getTime()));
logger.info(dateFormatter.format(newYearsEve));
assertTrue(newYearsEve.before(newYearsDay.getTime()));
}
Output
01/01/2013 00:00:00 CST
12/31/2012 23:59:59 CST