Java GregorianCalendar getLeastMaximum()方法

java.util.GregorianCalendar.getLeastMaximum() 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低最大值。任何可能的时间值的最低最大值被定义为由get方法返回的最大值，并考虑到 getFirstDayOfWeek, getMinimalDaysInFirstWeek, getGregorianChange 和getTimeZone方法的当前值。

语法：

public int getMaximum(int calendarfield)

参数： 该函数接受一个整数类型的强制性参数calendarfield，指的是函数将返回其最低最大值的日历字段。

返回值： 该方法返回一个整数值，该值等于指定日历字段的最低最大值。

示例：

Input : DAY_OF_MONTH
Output : 28

Input : WEEK_OF_MONTH
Output : 3

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

程序1：

// Java program to illustrate getLeastMaximum()
 
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 lowest maximum for WEEK_OF_MONTH
      int maxm = cal.getLeastMaximum(
                   GregorianCalendar.WEEK_OF_MONTH);
      System.out.println("Lowest Maximum for"+
                   " WEEK_OF_MONTH field :" + maxm);
 
      // Get lowest maximum for DAY_OF_MONTH
      maxm = cal.getLeastMaximum(
                    GregorianCalendar.DAY_OF_MONTH);
      System.out.println("Lowest Maximum for"+
                     " DAY_OF_MONTH field:" + maxm);
   }
}

输出

Current Date and Time : Wed Aug 01 06:48:43 UTC 2018
Lowest Maximum for WEEK_OF_MONTH field :3
Lowest Maximum for DAY_OF_MONTH field:28

程序2：

// Java program to illustrate getLeastMaximum()
 
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 lowest maximum for YEAR
      int maxm = cal.getLeastMaximum(
                           GregorianCalendar.YEAR);
      System.out.println("Lowest Maximum for"+
                           " YEAR field :" + maxm);
 
      // Get lowest maximum for HOUR_OF_DAY
      maxm = cal.getLeastMaximum(
                    GregorianCalendar.HOUR_OF_DAY);
      System.out.println("Lowest Maximum for"+
                     " HOUR_OF_DAY field:" + maxm);
   }
}

输出

Current Date and Time : Wed Aug 01 06:48:45 UTC 2018
Lowest Maximum for YEAR field :292269054
Lowest Maximum for HOUR_OF_DAY field:23

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