打印当月日历（GregorianCalendar）

import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import sun.util.calendar.Gregorian;

public class Test {
    public static void main(String[] args){
        GregorianCalendar gc = new GregorianCalendar();
        //获取当天日期和月份
        int today = gc.get(Calendar.DAY_OF_MONTH);
        int month = gc.get(Calendar.MONTH);
        //设置日期为当月1号
        gc.set(Calendar.DAY_OF_MONTH, 1);
     
        //获取当月1号的为周几
        int weekday = gc.get(Calendar.DAY_OF_WEEK);
        //打印日历头
        System.out.println("星期日  星期一  星期二  星期三  星期四  星期五  星期六");
        for (int i = Calendar.SUNDAY; i < weekday; i++) {
            System.out.print("        ");

        }

　　　//打印日历
        while (gc.get(Calendar.MONTH) == month) {
            int day = gc.get(Calendar.DAY_OF_MONTH);
            if (day<10) {
                if (day == today) {
                System.out.print("<"+day+">     ");
                }
                else{
                    System.out.print(" "+day+"      ");
                }
            }
            else{
                 if (day == today) {
                System.out.print("<"+day+">    ");
                }
                else{
                    System.out.print(" "+day+"     ");
                }
            }
          
            if (gc.get(Calendar.DAY_OF_WEEK) == 7) {
                System.out.println();
            }
            gc.add(Calendar.DAY_OF_MONTH, 1);
        }
       
    }
}

运行结果：

星期日  星期一  星期二  星期三  星期四  星期五  星期六
            1        2         3         4        5         6     
 7         8        9         10     <11>    12       13    
 14       15      16        17      18       19       20    
 21       22      23        24      25       26       27    
 28       29      30