显示日历---Java程序--请高手帮忙纠错

我向编写一个输入年与月后显示该月的日历，但是不知道错误在哪里，请高手帮忙！！！

下面为源程序代码（NewCalendar.java）：：

import javax.swing.JOptionPane;
public class NewCalendar{
public static void main(String[] args){
String yearString = JOptionPane.showInputDialog("Enter the year,for example 2009:");
int year = Integer.parseInt(yearString);
String monthString = JOptionPane.showInputDialog("Enter the month from 1 to 12:");
int month = Integer.parseInt(monthString);
printMonth(year,month);
}
/**print month*/
static void printMonth(int year ,int month){
printMonthTitle (year,month);
printMonthBody (year,month);
}
/**print month title*/
static void printMonthTitle (int year,int month){
String monthString = getMonthName(month);
System.out.println(" " + monthString + " " + year);
System.out.println("---------------------------------------------");
System.out.println(" Sun Mon Tue Wed Thu Fri Sat");
}
/** get month name*/
static String getMonthName (int month){
String monthString = null;
switch (month)
{case 1:monthString = "January";break;
case 2:monthString = "February";break;
case 3:monthString = "March";break;
case 4:monthString = "April";break;
case 5:monthString = "May";break;
case 6:monthString = "June";break;
case 7:monthString = "July";break;
case 8:monthString = "August";break;
case 9:monthString = "September";break;
case 10:monthString = "October";break;
case 11:monthString = "December";break;
case 12:monthString = "November";break;
}
return monthString;
}
/**print month body*/
static void printMonthBody(int year,int month){
int startDay = getStartDay (year,month);
int i = 0;
for (i = 0;i < startDay;i ++)
System.out.print(" ");
int monthOfDays = getMonthOfDays(year,month);
for (i = 1;i <= monthOfDays;i ++)
{if(i < 10)
System.out.print(" " + i);
else System.out.print(" " + i);
if ((i + startDay) % 7 ==0)
System.out.println();
}
System.out.print("/n");
}
/**get start day*/
static int getStartDay (int year,int month){
int totalOfDays = getTotalOfDays (year,month);
int startDay1800 = 3;
return (totalOfDays + startDay1800) % 7;
}
/**get total of days*/
static int getTotalOfDays (int year,int month){
int totalOfDays = 0;
for (int i = 1800;i < year;i ++)
totalOfDays +=isLeapYear(year) ? 366 :365;
for (int i = 1;i < month;i ++)
totalOfDays +=getMonthOfDays(year,i);
return totalOfDays;
}
/**get month of days*/
static int getMonthOfDays(int year,int month){
int monthOfDays = 0 ;
if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month ==12)
monthOfDays = 31;
if (month == 4 || month == 6 || month ==9 || month == 11)
monthOfDays = 30;
if (month == 2) monthOfDays = isLeapYear(year) ? 29 : 28;
return monthOfDays;
}

/** isLeaYear*/
static boolean isLeapYear (int year) {
return (year % 4 == 0 && year % 100 != 0) || year % 400 == 0;
}
}