（Java）打印指定年月的日历


日历如下：



程序如下：

//打印指定年月的日历
public class PrintCalendar {

public static void main(String[] args) {
int year=2013;
int month=12;
printMonth(year,month);
}

private static void printMonth(int year, int month) {//打印日历
printMonthTitle(year,month);
printMonthBody(year,month);
}

private static void printMonthTitle(int year, int month) {//打印日历标题
System.out.println(" "+getMonthName(month)+" "+year);
System.out.println("------------------------------");
System.out.println(" Sun Mon Tue Wed Thu Fri Sat");
}

private static String getMonthName(int month) {
String monthName=null;
switch(month){
case 1:monthName="January";break;
case 2:monthName="February";break;
case 3:monthName="March";break;
case 4:monthName="April";break;
case 5:monthName="May";break;
case 6:monthName="June";break;
case 7:monthName="July";break;
case 8:monthName="August";break;
case 9:monthName="September";break;
case 10:monthName="October";break;
case 11:monthName="November";break;
case 12:monthName="December";
}
return monthName;
}

public static boolean isLeapYear(int year){//判断是否为闰年
return year%400==0||(year%4==0&&year%100!=0);
}

public static int getNumberOfDaysInMonth(int year,int month){//获取对应月份天数
if(month==1||month==3||month==5||month==7||month==8||month==10||month==12)
return 31;
if(month==4||month==6||month==9||month==11)
return 30;
if(month==2)
return isLeapYear(year)?29:28;
return 0;
}

public static int getTotalNumberOfDays(int year,int month){//获取从1800年到当月的总天数
int total=0;
for(int i=1800;i<year;i++){
if(isLeapYear(i))
total=total+366;
else
total=total+365;
}
for(int i=1;i<month;i++)
total=total+getNumberOfDaysInMonth(year,i);
return total;
}

public static int getStartDay(int year,int month){//获得当月第一天是星期几
int startDay1800=3;
int totalNumberOfDays=getTotalNumberOfDays(year,month);
return (totalNumberOfDays+startDay1800)%7;
}

public static void printMonthBody(int year,int month){//打印日历体
int startDay=getStartDay(year,month);
int numberOfDaysInMonth=getNumberOfDaysInMonth(year,month);
for(int i=0;i<startDay;i++){
System.out.print(" ");
}
for(int 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();
}
}