Java操作时间

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

/**
 * @author Administrator
 */
public class OperationTime {

 /**
  *
  */
 public OperationTime() {
 // TODO Auto-generated constructor stub
 }

 /**
  * @param args
  */
 public static void main(String[] args) {
  try {
   java.text.SimpleDateFormat sdf = new java.text.SimpleDateFormat("M/dd/yyyy hh:mm:ss a",java.util.Locale.US);
   java.util.Date d = sdf.parse("5/13/2003 10:31:37 AM");
   System.out.println(d);
   System.out.println("<br>");
   SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
   String mDateTime1=formatter.format(d);
   System.out.println(mDateTime1);
   System.out.println("<br>");
   System.out.println(d.getTime());
   System.out.println("<br>");

   //当前时间
   Calendar cal = Calendar.getInstance();
   // SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
   //SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss G E D F w W a E F");
   String mDateTime=formatter.format(cal.getTime());
   System.out.println(mDateTime);
   System.out.println("<br>");

   //1年前日期
   java.util.Date myDate=new java.util.Date();
   long myTime=(myDate.getTime()/1000)-60*60*24*365;
   myDate.setTime(myTime*1000);
   String mDate=formatter.format(myDate);
   System.out.println(mDate);
   System.out.println("<br>");

   //明天日期
   myDate=new java.util.Date();
   myTime=(myDate.getTime()/1000)+60*60*24;
   myDate.setTime(myTime*1000);
   mDate=formatter.format(myDate);
   System.out.println(mDate);
   System.out.println("<br>");

   //两个时间之间的天数
   SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
   java.util.Date date= myFormatter.parse("2003-05-1");
   java.util.Date mydate= myFormatter.parse("1899-12-30");
   long day=(date.getTime()-mydate.getTime())/(24*60*60*1000);
   System.out.println(day);
   System.out.println("<br>");

   //加半小时
   SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
   java.util.Date date1 = format.parse("2002-02-28 23:16:00");
   long Time=(date1.getTime()/1000)+60*30;
   date1.setTime(Time*1000);
   String mydate1=formatter.format(date1);
   System.out.println(mydate1);
   System.out.println("<br>");

   //年月周求日期
   SimpleDateFormat formatter2 = new SimpleDateFormat("yyyy-MM F E");
   java.util.Date date2= formatter2.parse("2003-05 5 星期五");
   SimpleDateFormat formatter3 = new SimpleDateFormat("yyyy-MM-dd");
   String mydate2=formatter3.format(date2);
   System.out.println(mydate2);
   System.out.println("<br>");

   //求是星期几
   mydate= myFormatter.parse("2001-1-1");
   SimpleDateFormat formatter4 = new SimpleDateFormat("E");
   String mydate3=formatter4.format(mydate);
   System.out.println(mydate3);
   System.out.println("<br>");
  } catch (ParseException e) {
   e.printStackTrace();
  }
 }
}