计算Java中的闰年 [英] Calculate leap year in Java

问题描述

可能重复：

Java代码计算闰年，这个代码是否正确？

这是家庭作业，我已经收到了成绩，但我没有在我的代码中实现闰年。这是一个简单的程序，显示基于用户输入的一个月中的数字。唯一的事情是我不能弄清楚是一个实现一个闰年，将获得29天的二月而不是28，没有写多个 if 语句。当然有一个更容易的方法？下面是代码：

  //显示一个月中的天数
 
 package chapter_3; 
 
 import java.util.Scanner; 
 
 
 public class Chapter_3 {
 
 public static void main（String [] args）{
 System.out.println（ \\\

 +一个月的天数基于\\\

 +您的输入，当提示时请输入\\\

 +的数值你想要的月份\\\

 +查看包括年份例如：如果你想要\\\

 +查看三月进入3 2011等等。 
 
扫描仪输入= new Scanner（System.in）; 
 
 //提示用户输入月份和年份
 System.out.print（请输入月份和年份：）; 
 int month = input.nextInt（）; 
 int year = input.nextInt（）; 
 
 if（month == 1）{
 System.out.println（January+ year +has 31 days）; 
} 
 else if（month == 2）{
 System.out.println（February+ year +have 28 days）; 
} 
 else if（month == 3）{
 System.out.println（March+ year +has 31 days）; 
} 
 else if（month == 4）{
 System.out.println（April+ year +has 30 days）; 
} 
 else if（month == 5）{
 System.out.println（May+ year +has 31 days）; 
} 
 else if（month == 6）{
 System.out.println（June+ year +has 30 days）; 
} 
 else if（month == 7）{
 System.out.println（July+ year +has 31 days）; 
} 
 else if（month == 8）{
 System.out.println（August+ year +has 31 days）; 
} 
 else if（month == 9）{
 System.out.println（September+ year +has 30 days）; 
} 
 else if（month == 10）{
 System.out.println（October+ year +has 30 days）; 
} 
 else if（month == 11）{
 System.out.println（November+ year +has 30 days）; 
} 
 else if（month == 12）{
 System.out.println（December+ year +has 31 days）; 
} 
 else {
 System.out.println（请输入您要查看的月份的数值
 +）; 
} 
} 
} 
  

解决方案>

如果您使用 GregorianCalendar ，您可以按照以下方式进行：

确定给定年份是否为闰年。如果给定的
年是闰年，则返回true。要指定BC年数，1年数必须给出
。例如，年份BC 4指定为-3。

  GregorianCalendar cal = new GregorianCalendar ）; 
 
 if（cal.isLeapYear（year））
 {
 System.out.print（给定年份是闰年。 
} 
 else 
 {
 System.out.print（给定年份不是闰年。 
} 
  

Possible Duplicate:
Java Code for calculating Leap Year, is this code correct?

This was homework, and I have already received my grade, but I did not implement leap years in my code. This is a simple program that displays the numbers in a month based on user input. The only thing is I can't figure out is a way to implement a leap year that would get 29 days for February rather than 28, without writing multiple if statements. Surely there is an easier way? Here is the code:

//Displays number of days in a month

package chapter_3;

import java.util.Scanner;


public class Chapter_3 {

    public static void main(String[] args) {
        System.out.println("This program will calculate \n"
                + "the number of days in a month based upon \n"
                + "your input, when prompted please enter \n"
                + "the numerical value of the month you would like\n"
                + "to view including the year. Example: if you would like\n"
                + "to view March enter 3 2011 and so on.");

        Scanner input = new Scanner(System.in);

        //Prompt user for month and year
        System.out.print("Please enter the month and year: ");
        int month = input.nextInt();
        int year = input.nextInt();

        if (month == 1) {
            System.out.println("January " + year + " has 31 days");
        }   
        else if (month == 2) {
            System.out.println("February " + year + " has 28 days");
        }   
        else if (month == 3) {
            System.out.println("March " + year + " has 31 days");
        }
        else if (month == 4) {
            System.out.println("April " + year + " has 30 days");
        }
        else if (month == 5) {
            System.out.println("May " + year + " has 31 days");
        }
        else if (month == 6) {
            System.out.println("June " + year + " has 30 days");
        }
        else if (month == 7) {
            System.out.println("July " + year + " has 31 days");
        }
        else if (month == 8) {
            System.out.println("August " + year + " has 31 days");
        }
        else if (month == 9) {
            System.out.println("September " + year + " has 30 days");
         }
        else if (month == 10) {
            System.out.println("October " + year + " has 30 days");
        }
        else if (month == 11) {
            System.out.println("November " + year + " has 30 days");
        }
        else if (month == 12) {
            System.out.println("December " + year + " has 31 days");
         }
        else {
            System.out.println("Please enter the numerical value "
                + "of the month you would like to view");
        }
    }
}        

解决方案

If you use the GregorianCalendar, you could do as below

Determines if the given year is a leap year. Returns true if the given year is a leap year. To specify BC year numbers, 1 - year number must be given. For example, year BC 4 is specified as -3.

GregorianCalendar cal = new GregorianCalendar();

if(cal.isLeapYear(year))
{
    System.out.print("Given year is leap year.");
}
else
{ 
    System.out.print("Given year is not leap year.");
}

这篇关于计算Java中的闰年的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！