我需要从命令行打印给定输入的日历。我遇到的主要问题是尝试打印日历的实际正文。我有一个方法：
printMonth();
用于打印日历。该方法是无效且非静态的。但是，当我从main（静态）调用该方法时，没有输出。
到目前为止是我的代码：
class MyDate {
private int day;
private int month;
private int year;
public MyDate(int theDay, int theMonth, int theYear){
theDay = day;
theMonth = month;
theYear = year;
}
public MyDate(){
}
public int getDay() {
return day;
}
public int getMonth() {
return month;
}
public String nameOfMonth() {
switch (month) {
case 1:
return "January";
case 2:
return "February";
case 3:
return "March";
case 4:
return "April";
case 5:
return "May";
case 6:
return "June";
case 7:
return "July";
case 8:
return "August";
case 9:
return "September";
case 10:
return "October";
case 11:
return "November";
case 12:
return "December";
// for any number less than 1 and greater than 12 throw an exception
default:
throw new RuntimeException("Invalid month number");
}
}
public int getYear() {
return year;
}
public String getDate(String[] datePartsObj) {
day = Integer.parseInt(datePartsObj[0]);
month = Integer.parseInt(datePartsObj[1]);
year = Integer.parseInt(datePartsObj[2]);
return day + "/" + month + "/" + year ;
}
public int getStartDay(int theYear, int theMonth) {
year = theYear;
month = theMonth;
// Get total number of days since 1/1/1800
int startDay1800 = 3;
int totalNumberOfDays = getTotalNumberOfDays(theYear, theMonth);
// Return the start day
return (totalNumberOfDays + startDay1800) % 7;
}
public int getTotalNumberOfDays(int theYear, int theMonth) {
year = theYear;
month = theMonth;
int total = 0;
// Get the total days from 1800 to year - 1
for (int i = 1800; i < theYear; i++)
if (isLeapYear(i))
total = total + 366;
else
total = total + 365;
// Adding days from January to the month prior to the calendar month
for (int i = 1; i < theMonth; i++)
total = total + getNumberOfDaysInMonth(theYear, i);
return total;
}
public int getNumberOfDaysInMonth(int theMonth, int theYear) {
month = theMonth;
year = theYear;
if (theMonth == 1 || theMonth == 3 || theMonth == 5 || theMonth == 7 ||
theMonth == 8 || theMonth == 10 || theMonth == 12)
return 31;
if (theMonth == 4 || theMonth == 6 || theMonth == 9 || theMonth == 11)
return 30;
if (theMonth == 2) return isLeapYear(theYear) ? 29 : 28;
return 0; // If month is incorrect
}
public boolean isLeapYear(int theYear) {
year = theYear;
if ((theYear % 4 == 0) && (theYear % 100 != 0)) return true;
if (theYear % 400 == 0) return true;
return false;
}
}
public class MyCalendar {
private static MyDate myDateObj;
public enum WeekDay{
Monday,
Tuesday,
Wednesday,
Thursday,
Friday,
Saturday,
Sunday;
}
public MyCalendar(MyDate newdate){
}
public MyCalendar(){
}
public int weekOfMonth() {
return;
}
public void printMonth() {
int theYear = myDateObj.getYear();
int theMonth = myDateObj.getMonth();
// Get start day of the week for the first date in the month
int startDay = myDateObj.getStartDay(theYear, theMonth);
// Get number of days in the month
int numberOfDaysInMonth = myDateObj.getNumberOfDaysInMonth(theYear, theMonth);
// Pad space before the first day of the month
int i = 0;
for (i = 0; i < startDay; i++)
System.out.print(" ");
for (i = 1; i <= numberOfDaysInMonth; i++) {
if (i < 10)
System.out.print(" " + i);
else
System.out.print(" " + i);
if ((i + startDay) % 7 == 0)
System.out.println();
}
System.out.println();
}
public static void main(String [] args) {
String[] datePartsObj;
datePartsObj = args[0].split("/");
int day = Integer.parseInt(datePartsObj[0]);
int month = Integer.parseInt(datePartsObj[1]);
int year = Integer.parseInt(datePartsObj[2]);
myDateObj = new MyDate(day, month, year);
MyCalendar myCalendar = new MyCalendar();
System.out.println(myDateObj.getDate(datePartsObj) + " is a " + " and locates in the " + myDateObj.nameOfMonth());
myDateObj.nameOfMonth();
System.out.println("The calendar of " + myDateObj.nameOfMonth() + " " + myDateObj.getYear() + " is: ");
System.out.println();
System.out.println(" Sun Mon Tue Wed Thu Fri Sat");
myCalendar.printMonth();
}
}
我对Java还是很陌生，因此非常感谢您解决此问题！
在您的方法printMonth()中，您已经调用了方法getNumberOfDaysInMonth(theMonth, theYear)，并且您以错误的顺序传递了参数
更改此行：
int numberOfDaysInMonth = myDateObj.getNumberOfDaysInMonth(theYear, theMonth);
至此：
int numberOfDaysInMonth = myDateObj.getNumberOfDaysInMonth(theMonth, theYear);