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Java program to add two dates

Comprehensive Java Examples

In this program, you will learn how to add two dates together in Java using Calendar.

Because the Java era is1970 years, so any time represented by a Date object does not work. This means that your date will start1970 years, when two date objects are added together, the sum will lose approximately1970 years. So, we use Calendar instead.

Example: Adding two dates

import　java.util.Calendar;
public　class　AddDates　{
　　　　public　static　void　main(String[]　args)　{
　　　　　　　　Calendar　c1　=　Calendar.getInstance();
　　　　　　　　Calendar　c2　=　Calendar.getInstance();
　　　　　　　　Calendar　cTotal　=　(Calendar)　c1.clone();
　　　　　　　　cTotal.add(Calendar.YEAR,　c2.get(Calendar.YEAR));
　　　　　　　　cTotal.add(Calendar.MONTH,　c2.get(Calendar.MONTH)　+　1);　//　Month starting from zero
　　　　　　　　cTotal.add(Calendar.DATE,　c2.get(Calendar.DATE));
　　　　　　　　cTotal.add(Calendar.HOUR_OF_DAY,　c2.get(Calendar.HOUR_OF_DAY));
　　　　　　　　cTotal.add(Calendar.MINUTE, c2.get(Calendar.MINUTE));
　　　　　　　　cTotal.add(Calendar.SECOND, c2.get(Calendar.SECOND));
　　　　　　　　cTotal.add(Calendar.MILLISECOND, c2.get(Calendar.MILLISECOND));
　　　　　　　　System.out.format("%s　+　%s = %s", c1.getTime(), c2.getTime(), cTotal.getTime());
　　　　}
}

When you run the program, the output is:

Tue Aug 08　10:20:56　NPT　2017　+　Tue Aug 08　10:20:56　NPT　2017　= Mon Apr　16　20:41:53　NPT　4035

In the above program, c1and c2. Then, we simply clone c1, and store the current date in c2each DateTime attribute one by one.

As you can see, we increase1This is because the month starts from 0 in Java.

Comprehensive Java Examples

Java Method Overloading Comprehensive Java Examples