在看一个21java代码包 里面有一段 输入年 月后判断该月有几天的代码
class DayCounter {
public static void main(String[] arguments) {
int yearIn = 2001;
int monthIn = 2;
if (arguments.length > 0)
monthIn = Integer.parseInt(arguments[0]);
if (arguments.length > 1)
yearIn = Integer.parseInt(arguments[1]);
System.out.println(monthIn + "/" + yearIn + " has "
+ countDays(monthIn, yearIn) + " days.");
} static int countDays(int month, int year) {
int count = -1;
switch (month) {
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
count = 31;
break;
case 4:
case 6:
case 9:
case 11:
count = 30;
break;
case 2:
if (year % 4 == 0)
count = 29;
else
count = 28;
if ((year % 100 == 0) & (year % 400 != 0))
count = 28;
}
return count;
}
}那两行if语句是做什么用的?
class DayCounter {
public static void main(String[] arguments) {
int yearIn = 2001;
int monthIn = 2;
if (arguments.length > 0)
monthIn = Integer.parseInt(arguments[0]);
if (arguments.length > 1)
yearIn = Integer.parseInt(arguments[1]);
System.out.println(monthIn + "/" + yearIn + " has "
+ countDays(monthIn, yearIn) + " days.");
} static int countDays(int month, int year) {
int count = -1;
switch (month) {
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
count = 31;
break;
case 4:
case 6:
case 9:
case 11:
count = 30;
break;
case 2:
if (year % 4 == 0)
count = 29;
else
count = 28;
if ((year % 100 == 0) & (year % 400 != 0))
count = 28;
}
return count;
}
}那两行if语句是做什么用的?
if (arguments.length > 0)
monthIn = Integer.parseInt(arguments[0]);
if (arguments.length > 1)
yearIn = Integer.parseInt(arguments[1]);
System.out.println(monthIn + "/" + yearIn + " has "
+ countDays(monthIn, yearIn) + " days.");
btw 怎么在代码框里加色?
if (arguments.length > 0)
monthIn = Integer.parseInt(arguments[0]);
if (arguments.length > 1)
yearIn = Integer.parseInt(arguments[1]);
这2行的含义是这样子的 再我们开始学java的时候是使用Windows的命令行在里面输入命令进行编译 运行java代码 java中 main方法是程序的执行入口,public static void main(String[] arguments)中 字符串数组 arguments用于接收我们输入的控制台参数 具体如何使用你可以上GOOGLE 搜索一下相关资料