java 输入某年某月某日，判断这一天是这一年的第几天

importjava.util.*;

publicclasstest {

  publicstaticvoidmain (String[]args){

    intday=0;

    intmonth=0;

    intyear=0;

    intsum=0;

    intleap;

    System.out.print("请输入年,月,日n");

    Scanner input =newScanner(System.in);

    year=input.nextInt();

    month=input.nextInt();

    day=input.nextInt();

    switch(month)/*先计算某月以前月份的总天数*/

    {

    case 1:

      sum=0;break;

    case 2:

      sum=31;break;

    case 3:

      sum=59;break;

    case 4:

      sum=90;break;

    case 5:

      sum=120;break;

    case 6:

      sum=151;break;

    case 7:

      sum=181;break;

    case 8:

      sum=212;break;

    case 9:

      sum=243;break;

    case 10:

      sum=273;break;

    case 11:

      sum=304;break;

    case 12:

      sum=334;break;

    default:

      System.out.println("data error");break;

    }

    sum=sum+day; /*再加上某天的天数*/

    if(year%400==0||(year%4==0&&year%100!=0))/*判断是不是闰年*/

      leap=1;

    else

      leap=0;

    if(leap==1 && month>2)/*如果是闰年且月份大于2,总天数应该加一天*/

      sum++;

    System.out.println("It is the the day:"+sum);

    }

}