Java8新特性 - 日期相关 - 日期加减

1. 日期相减
DateDiff.java

package corejava2.date;

import java.time.LocalDate;
import java.time.Period;

public class DateDiff {

	public static void main(String[] args) {
		/** The date at the end of the last century */
		LocalDate endofCentury = LocalDate.of(2000, 12, 31);
		LocalDate now = LocalDate.now();

		Period diff = Period.between(endofCentury, now);

		System.out.printf("The 21st century (up to %s) is %s old%n", now, diff);
		System.out.printf("The 21st century is %d years, %d months and %d days old",
				diff.getYears(), diff.getMonths(), diff.getDays());
	}
}

运行结果:
The 21st century (up to 2015-10-06) is P14Y9M6D old
The 21st century is 14 years, 9 months and 6 days old

2. 日期相加
DateAdd.java

package corejava2.date;

import java.time.LocalDate;
import java.time.Period;

/**
 * DateAdd -- compute the difference between two dates (e.g., today and 700 days
 * from now).
 */
public class DateAdd {
	public static void main(String[] av) {
		/** Today's date */
		LocalDate now = LocalDate.now();

		Period p = Period.ofDays(700);
		LocalDate then = now.plus(p);

		System.out.printf("Seven hundred days from %s is %s%n", now, then);
	}
}

运行结果:
Seven hundred days from 2015-10-06 is 2017-09-05