用java程序判断输入年份是否为闰年，如果输入错误，能重新输入，知道输入正确为止

public class Bissextile {
public static void main(String[] args) {
Bissextile instance = new Bissextile();
while (!instanceisBissextile()) {
Systemoutprintln("不是闰年\n");
}
Systemoutprintln("是闰年");
}
private boolean isBissextile() {
Systemoutprintln("请输入年份:");
Scanner scanner = new Scanner(Systemin);
int year = scannernextInt();
return (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
}
}

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@author qingsongwang

/
import javautil;
public class B {
public static boolean isRun(int year)
{
return (year % 4 != 0 )|| (year % 100 == 0 )&& (year % 400 != 0);

}
public static void main(String[] args) {
Scanner input=new Scanner(Systemin);
int year;
Systemoutprintf("你输入的年份是：%s", year=inputnextInt());
if(isRun(year)){
Systemoutprint("(是闰年)");
}
else{
Systemoutprint("(不是闰年)");
}
}
}
直接运行这个程序即可！

今年的年数和月数知道吧？
看月数是否小于或等于2，如果是就判断今年是否闰年，如果否判断明年是否闰年
如果前面的判断闰年为真，那么明年的今天 就是当前的时间+ 3662436001000
如果闰年判断为假就是365243600100了
判断当年：
年数=n
是否闰年 = ((n/4==0 && n/100!=0) || n/400 == 0)
public static void main(String[] args) {
Date now = new Date();
int nowYear = nowgetYear();
int month = nowgetMonth();
long addMillis = 0;
boolean isLeap = false;
if(month <= 2){
isLeap = ((nowYear%4==0 && nowYear%100!=0) || nowYear%400 == 0);
}else{
nowYear += 1;
isLeap = ((nowYear%4==0 && nowYear%100!=0) || nowYear%400 == 0);
}
if(isLeap){
addMillis = ((long)366)2436001000;
}else{
addMillis = ((long)365)2436001000;
}

Date nextYear = new Date(SystemcurrentTimeMillis() + addMillis);
Systemoutprintln(nextYear);
}

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