按照你的要求编写的Java程序如下
import java.util.Calendar;
import java.util.Scanner;
public class C{
public static void main(String[] args) {
String []week={"Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"};
System.out.print("Enter the year,month and day:");
Scanner sc=new Scanner(System.in);
int year=sc.nextInt();
int month=sc.nextInt();
int day=sc.nextInt();
int dayOfMonth=0;
Calendar c=Calendar.getInstance();
System.out.println("Month\t\tDays");
for(int i=1;i<=12;i++){
c.set(Calendar.YEAR, year);
c.set(Calendar.MONTH, (i-1));
dayOfMonth=c.getActualMaximum(Calendar.DAY_OF_MONTH);
System.out.println(i+"\t\t"+dayOfMonth);
}
c.clear();
c.set(Calendar.YEAR,year);
int dayOfYear=c.getActualMaximum(Calendar.DAY_OF_YEAR);
System.out.println("There are "+dayOfYear+" days in this year");
c.clear();
c.set(year,month-1,day);
int intWeek=c.get(Calendar.DAY_OF_WEEK)-1;
System.out.println("The day is a "+week[intWeek]);
}
}