Java GregorianCalendar getGreatestMinimum()方法

java.util.GregorianCalendar.getGreatestMinimum() 方法是Java中的一个内置函数，用于返回该GregorianCalendar实例中作为参数传递给函数的日历字段的最高最低值。任何可能的时间值的最高最小值被定义为由get方法返回的最小值，并考虑到getFirstDayOfWeek , getMinimalDaysInFirstWeek , getGregorianChange和getTimeZone方法的当前值。

语法

public int getGreatestMinimum(int calendarfield)

参数： 该函数接受一个整数类型的强制性参数calendarfield，其最高最小值将由该函数返回。

返回值： 该方法返回一个整数，表示指定日历域的最高最小值。

例子

Input : DAY_OF_MONTH
Output : 1

Input : WEEK_OF_MONTH
Output : 0

以下程序说明了java.util.GregorianCalendar.getGreatestMaximum()函数的工作情况：
程序1 :

// Java Program to illustrate getGreatestMinimum()
  
import java.io.*;
import java.util.*;
  
class GFG {
     public static void main(String[] args) {
      
      // Create a new calendar
      GregorianCalendar cal = (GregorianCalendar)
                  GregorianCalendar.getInstance();
  
      // Display the current date and time
      System.out.println("Current Date and Time : " 
                                   + cal.getTime());
  
      // Greatest minimum for WEEK_OF_MONTH
      int minm = cal.getGreatestMinimum(
                   GregorianCalendar.WEEK_OF_MONTH);
      System.out.println("Greatest Minimum for"+
                   " WEEK_OF_MONTH field :" + minm);
  
      // Get greatest minimum for DAY_OF_MONTH
      minm = cal.getGreatestMinimum(
                    GregorianCalendar.DAY_OF_MONTH);
      System.out.println("Greatest Minimum for"
                    +" DAY_OF_MONTH field:" + minm);
   }
}

输出。

Current Date and Time : Wed Aug 01 07:21:14 UTC 2018
Greatest Minimum for WEEK_OF_MONTH field :0
Greatest Minimum for DAY_OF_MONTH field:1

程序2

// Java Program to illustrate getGreatestMinimum()
  
import java.io.*;
import java.util.*;
  
class GFG {
     public static void main(String[] args) {
      
      // Create a new calendar
      GregorianCalendar cal = (GregorianCalendar)
                   GregorianCalendar.getInstance();
  
      // Display the current date and time
      System.out.println("Current Date and Time : "
                                  + cal.getTime());
  
      // Get greatest minimum for YEAR
      int minm = cal.getGreatestMinimum
                         (GregorianCalendar.YEAR);
      System.out.println("Greatest Minimum for"+
                           " YEAR field :" + minm);
  
      // Get greatest minimum for HOUR_OF_DAY
      minm = cal.getGreatestMinimum(
                    GregorianCalendar.HOUR_OF_DAY);
      System.out.println("Greatest Minimum for"+
                     " HOUR_OF_DAY field:" + minm);
   }
}

输出。

Current Date and Time : Wed Aug 01 07:21:16 UTC 2018
Greatest Minimum for YEAR field :1
Greatest Minimum for HOUR_OF_DAY field:0

**参考资料: ** https://docs.oracle.com/javase/7/docs/api/java/util/GregorianCalendar.html#getGreatestMinimum()