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Calendar ÀàÊÇÒ»¸ö³éÏóÀ࣬ËüÎªÌØ¶¨Ë²¼äÓëÒ»×éÖîÈç YEAR¡¢MONTH¡¢DAY_OF_MONTH¡¢HOUR µÈ ÈÕÀú×Ö¶ÎÖ®¼äµÄת»»ÌṩÁËһЩ·½·¨£¬²¢Îª²Ù×÷ÈÕÀú×ֶΣ¨ÀýÈç»ñµÃÏÂÐÇÆÚµÄÈÕÆÚ£©ÌṩÁËһЩ·½·¨¡£Ë²¼ä¿ÉÓúÁÃëÖµÀ´±íʾ£¬ËüÊǾàÀúÔª£¨¼´¸ñÁÖÍþÖαê׼ʱ¼ä 1970 Äê 1 Ô 1 ÈÕµÄ 00:00:00.000£¬¸ñÀï¸ßÀûÀú£©µÄÆ«ÒÆÁ¿¡£
Àý:
Calendar cal = Calendar.getInstance();//ʹÓÃĬÈÏÊ±ÇøºÍÓïÑÔ»·¾³»ñµÃÒ»¸öÈÕÀú¡£
cal.add(Calendar.DAY_OF_MONTH, -1);//È¡µ±Ç°ÈÕÆÚµÄǰһÌì.
cal.add(Calendar.DAY_OF_MONTH, +1);//È¡µ±Ç°Èͮ򵀼óÒ»Ìì.
//ͨ¹ý¸ñʽ»¯Êä³öÈÕÆÚ
java.text.SimpleDateFormat format = new java.text.SimpleDateFormat("yyyy-MM-dd");
System.out.println("Today is:"+format.format(Calendar.getInstance().getTime()));
System.out.println("yesterday is:"+format.format(cal.getTime()));
µÃµ½2007-12-25ÈÕÆÚ:
Calendar calendar = new GregorianCalendar(2007, 11, 25,0,0,0);
Date date = calendar.getTime();
System.out.println("2007 Christmas is:"+format.format(date));
//javaÔ·ÝÊÇ´Ó0-11,Ô·ÝÉèÖÃʱҪ¼õ1.
//GregorianCalendar¹¹Ôì·½·¨²ÎÊýÒÀ´ÎΪ£ºÄ꣬ÔÂ-1£¬ÈÕ£¬Ê±£¬·Ö£¬Ãë.
È¡ÈÕÆÚµÄ²¿·Ö:
int year =calendar.get(Calendar.YEAR);
int month=calendar.get(Calendar.MONTH)+1;
int day =calendar.get(Calendar.DAY_OF_MONTH);
int hour =calendar.get(Calendar.HOUR_OF_DAY);
int minute =calendar.get(Calendar.MINUTE);
int seconds =calendar.get(Calendar.SECOND);
ȡԷÝÒª¼Ó1.
Åжϵ±Ç°Ô·ݵÄ×î´óÌìÊý:
Calendar cal = Calendar.getInstance();
int day=cal.getActualMaximum(Calendar.DAY_OF_MONTH);
System.out.println(day);
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¾¡¹Ü Date Àà´òË㷴ӳЭµ÷ÊÀ½çʱ (UTC)£¬µ«ÎÞ·¨×öµ½Èç´Ë׼ȷ£¬ÕâÈ¡¾öÓÚ Java ÐéÄâ»úµÄÖ÷»ú»·¾³¡£µ±Ç°¼¸ºõËùÓвÙ×÷ϵͳ¶¼¼Ù¶¨ 1 Ìì = 24 × 60 × 60 = 86400 Ãë¡£µ«¶ÔÓÚ UTC£¬´óԼÿһÁ½Ä


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class Animal{}
class Fish extends Aniaml{}
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class Fish extends animal
{
 void output()
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  System.out.println("Fish");
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