Java 日历 add()方法及实例
Calendar类中的 add()方法用于根据日历的规则,从给定的日历字段(int field)中增加或减少特定的时间(int amt)。
语法
public abstract void add(int field , int amt)
参数: 该方法需要两个参数。
- 要对其进行操作的日历字段。(整数类型)
- 需要被减去的时间量。(整数类型)
返回值: 该方法不返回任何值。
例1 :
// Java Program to Illustrate add() Method
// of Calendar class
// Importing required classes
import java.util.Calendar;
// Main class
public class CalendarClassDemo {
// Main driver method
public static void main(String args[])
{
// Creating a Calendar class object
Calendar calndr = Calendar.getInstance();
// Displaying the current date
// using getTime() method
System.out.println("Current Date: "
+ calndr.getTime());
// Adding 50 days to the
// Current Calendar
// using add() method
calndr.add(Calendar.DATE, 50);
// Displaying the date now using getTime() method
System.out.println("After 50 days: "
+ calndr.getTime());
// Subtracting 6 months from
// the Current calendar
calndr.add(Calendar.MONTH, -6);
// Displaying the date now using getTime() method
System.out.println("6 months ago it was: "
+ calndr.getTime());
// Subtracting 2 year from
// the Current calendar
calndr.add(Calendar.YEAR, -2);
// Displaying the date now using getTime() method
System.out.println("2 years ago it was: "
+ calndr.getTime());
}
}
输出
Current Date: Tue Feb 12 10:54:21 UTC 2019
After 50 days: Wed Apr 03 10:54:21 UTC 2019
6 months ago it was: Wed Oct 03 10:54:21 UTC 2018
2 years ago it was: Mon Oct 03 10:54:21 UTC 2016
例2 :
// Java Program to Illustrate add() Method
// of Calendar class
// Importing required classes
import java.util.Calendar;
// Main class
public class GFG {
// Main driver method
public static void main(String args[])
{
// Creating a calendar object
Calendar calndr = Calendar.getInstance();
// Displaying the current date
// using getTime() method
System.out.println("Current Date: "
+ calndr.getTime());
// Adding 30 days to the current calendar
// using add() method
calndr.add(Calendar.DATE, 30);
// Printing the corresponding date
System.out.println("After 30 days: "
+ calndr.getTime());
// Subtracting 3 months from the current calendar
calndr.add(Calendar.MONTH, -3);
// Printing the corresponding date
System.out.println("3 months ago it was: "
+ calndr.getTime());
// Subtracting 10 years from
// the Current calendar
calndr.add(Calendar.YEAR, -10);
// Printing the corresponding date
System.out.println("10 years ago it was: "
+ calndr.getTime());
}
}
输出
Current Date: Tue Feb 12 10:54:24 UTC 2019
After 30 days: Thu Mar 14 10:54:24 UTC 2019
3 months ago it was: Fri Dec 14 10:54:24 UTC 2018
10 years ago it was: Sun Dec 14 10:54:24 UTC 2008