GregoranCalandar类（java核心P103）

package com.cx.test;

import java.text.DateFormatSymbols;
import java.util.Calendar;
import java.util.GregorianCalendar;

public class CalendarTest {
	public static void main(String[] args) {
		GregorianCalendar d = new GregorianCalendar();
		
		int today = d.get(Calendar.DAY_OF_MONTH);
		int month = d.get(Calendar.MONTH);
		
		d.set(Calendar.DAY_OF_MONTH, 1);
		
		int weekday = d.get(Calendar.DAY_OF_WEEK);
	
		int firstDayOfWeek = d.getFirstDayOfWeek();
		
		int indent = 0;
		while (weekday != firstDayOfWeek)
		{
			indent++;
			d.add(Calendar.DAY_OF_WEEK, -1);
			weekday = d.get(Calendar.DAY_OF_WEEK);
		}
		
		String[] weekdayNames = new DateFormatSymbols().getShortWeekdays();
		do
		{
			System.out.printf("%4s",weekdayNames[weekday]);
			d.add(Calendar.DAY_OF_WEEK, 1);
			weekday = d.get(Calendar.DAY_OF_WEEK);
		}while(weekday != firstDayOfWeek);
		
		System.out.println();
		
		for (int i = 0; i < indent; i++)
		{
			System.out.print("    ");
		}
		d.set(Calendar.DAY_OF_MONTH, 1);
		do
		{
			int day = d.get(Calendar.DAY_OF_MONTH);
			System.out.printf("%3d", day);
			
			if(day == today) System.out.print("*");
			else System.out.print("  ");
			
			d.add(Calendar.DAY_OF_MONTH, 1);
			weekday = d.get(Calendar.DAY_OF_WEEK);
			
			if(weekday == firstDayOfWeek) System.out.println();
		}while(d.get(Calendar.MONTH) == month);
			
		if(weekday != firstDayOfWeek) System.out.println();
	}
}