常用类

时间类

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

import javax.print.SimpleDoc;

public class date {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Date s=new Date();
SimpleDateFormat sdf;
sdf=new SimpleDateFormat("yyy-MM-dd");
System.out.println(sdf.format(s));
String a="2016-04-14";

try {
System.out.println(sdf.parse(a));
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Calendar d=new GregorianCalendar();
Calendar c=new GregorianCalendar();
c.add(Calendar.DAY_OF_WEEK_IN_MONTH,-4
);
System.out.println(c.get(Calendar.DAY_OF_WEEK_IN_MONTH));
System.out.println(d.after(c));
Date d1=c.getTime();
}
}