Java Object-oriented _ Common class Library api--date Operation class

Data class

Class data represents a specific moment, accurate to milliseconds, which is the current time when the program is running

Data data=new data ();//Instantiate the data object representing the current time

Calendar class

Calendar class, which can be used to display the time exactly in milliseconds.

Two types of instantiation

Calendar c=calendar.getinstance ();//calendar class is an abstract class and cannot be directly new

Calendar c=new GregorianCalendar ();

DateFormat class and sub-class SimpleDateFormat

Cases:

1 ImportJava.text.SimpleDateFormat;2 Importjava.util.Date;3 ImportJava.util.Calendar;4 ImportJava.text.DateFormat;5 6 7  Public classDatautiles {8 9     /**Ten      * @paramargs One      */ A      Public Static voidMain (string[] args) { -         //TODO auto-generated Method Stub -Date d=NewDate (); the System.out.println (d); -          -Calendar c=calendar.getinstance (); -         intYear=c.get (calendar.year);//Get year +         intMonth=c.get (calendar.month) +1;//Month -         intDay=c.get (Calendar.day_of_month);//Day +         intWeek=c.get (Calendar.day_of_week)-1;//Week A         intHour=c.get (Calendar.hour_of_day);//when at         intMinute=c.get (Calendar.minute);//points -         intSecond=c.get (Calendar.second);//seconds -String[] weeks={"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"}; -SYSTEM.OUT.PRINTLN (year+ "year" +month+ "month" +day+ "Day" + "+weeks[week]+hour+": "+minute+": "+second); -         //use time date format mode -DateFormat df=NewSimpleDateFormat ("yyyy mm month DD Day HH:MM:SS SSS E"); inString Nowdate=df.format (NewDate ()); - System.out.println (nowdate); to          +         LongData2=system.currenttimemillis ();//represents the current system time (in milliseconds) - System.out.println (data2); the     } *  $}

Java Object-oriented _ Common class Library api--date Operation class