Calender

import java.util.Calendar;

/*
 * Calendar:            YEAR、MONTH、DAY_OF_MONTH、HOUR                   ，        （          ）       。
 * 
 * public int get(int field):          。                    ，   int  。
 */
public class CalendarDemo {
	public static void main(String[] args) {
		//                  ：
		Calendar rightNow = Calendar.getInstance(); //     

		//    
		int year = rightNow.get(Calendar.YEAR);
		//    
		int month = rightNow.get(Calendar.MONTH);
		//    
		int date = rightNow.get(Calendar.DATE);

		System.out.println(year + " " + (month + 1) + " " + date + " ");//month    0
	}
}

/*
 * abstract class Person { public static Person getPerson() { return new
 * Student(); } }
 * 
 * class Student extends Person {
 * 
 * }
 */


//     （     ，  ）
<pre name="code" class="java">import java.util.Calendar;

/*
 * public void add(int field,int amount):               ，           。
 * public final void set(int year,int month,int date):          
 */
public class CalendarDemo {
	public static void main(String[] args) {
		//          
		Calendar c = Calendar.getInstance();

		//    
		int year = c.get(Calendar.YEAR);
		//    
		int month = c.get(Calendar.MONTH);
		//    
		int date = c.get(Calendar.DATE);
		System.out.println(year + " " + (month + 1) + " " + date + " ");

		// //       
		// c.add(Calendar.YEAR, -3);
		// //    
		// year = c.get(Calendar.YEAR);
		// //    
		// month = c.get(Calendar.MONTH);
		// //    
		// date = c.get(Calendar.DATE);
		// System.out.println(year + " " + (month + 1) + " " + date + " ");

		// 5   10  
		c.add(Calendar.YEAR, 5);
		c.add(Calendar.DATE, -10);
		//    
		year = c.get(Calendar.YEAR);
		//    
		month = c.get(Calendar.MONTH);
		//    
		date = c.get(Calendar.DATE);
		System.out.println(year + " " + (month + 1) + " " + date + " ");
		System.out.println("--------------");

		c.set(2011, 11, 11);
		//    
		year = c.get(Calendar.YEAR);
		//    
		month = c.get(Calendar.MONTH);
		//    
		date = c.get(Calendar.DATE);
		System.out.println(year + " " + (month + 1) + " " + date + " ");
	}
}