chuchichaeschtli chuchichaeschtli - 8 months ago 41
Java Question

Min/Max Date/DateTime in JodaTime

Is there any way in JodaTime to construct a Date/DateTime which will always be smaller/larger than any other Date/DateTime? Something along the lines of

DateTime bigBang =;
DateTime endOfUniverse = DateTime.yyy();

Constraint: I don't want to use the standard Java Date libraries.


Joda-Time tracks time as a count of milliseconds since the epoch of first moment of 1970 in UTC. This count is kept using a 64-bit long integer. So, technically, the maximum and minimums are the +/- limits of a long.

… new DateTime( Long.MIN_VALUE )
… new DateTime( Long.MAX_VALUE )

Joda-Time has no such minimum/maximum values available conveniently as constants. In contrast, note that Joda-Time’s successor, java.time built into Java 8 and later, does indeed offer the constants LocalDateTime.MIN and LocalDateTime.MAX.

By the way, the Joda-Time team has advised we should migrate to java.time. Much of the java.time functionality is back-ported to Java 6 & 7 in the ThreeTen-Backport, further adapted to Android in ThreeTen-ABP.

Too big, too small

Beware of these extremes. Their use is not practical. Various libraries, apps, databases, and other sinks/sources of date-time values may have much different limits, some much larger but typically much smaller.

For example, many systems use the old tradition from UNIX & POSIX of tracking time as a 32-bit integer count of whole seconds since 1970-01-01T00:00:00Z. The natural limit of +/- two billion seconds results in the looming Year 2038 Problem.

Another limit is the physical display size of fields on forms and reports that expect only four digits in a year number.


You can define your own min/max.

You may want extreme values such as year 0000 and year 9999. Joda-Time supports years later than 9,999 but I would stick with 4 digits to fit the commonly used formats for display on-screen and in reports. Visually, the four nines stand out as a bogus date.

Or you may want an expected minimum value appropriate to your business logic. If building a new invoicing system, then you know the year should always be this year or later.

I suggest defining constants on a helper class. Something like this:

package com.example;

import org.joda.time.DateTime;
import org.joda.time.DateTimeZone;

public class JodaTimeHelper {

    static final public DateTime START_OF_TIME = new DateTime( 0000, 1, 1, 0, 0, 0, DateTimeZone.UTC );
    static final public DateTime END_OF_TIME = new DateTime( 9999, 1, 1, 0, 0, 0, DateTimeZone.UTC );

    static final public DateTime MINIMUM_INVOICE_DATETIME = new DateTime( 2015, 1, 1, 0, 0, 0, DateTimeZone.UTC );


Here is the syntax for calling those constants.

System.out.println( "START_OF_TIME: " + JodaTimeHelper.START_OF_TIME );
System.out.println( "END_OF_TIME: " + JodaTimeHelper.END_OF_TIME );
System.out.println( "END_OF_TIME: " + JodaTimeHelper. MINIMUM_INVOICE_DATETIME );

When run.

START_OF_TIME: 0000-01-01T00:00:00.000Z
END_OF_TIME: 9999-01-01T00:00:00.000Z
MINIMUM_INVOICE_DATETIME: 2015-01-01T00:00:00.000Z