import java.sql.Timestamp; import java.text.DateFormat; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; public class DateIO { public static void main(String[] args) { Date date= new  DateIO().strToDate("2013-04-01"); String strdate=new DateIO().dateToStr(date); String srrdate=new DateIO().timestampToStr(System.currentTimeMillis()); Timestamp ts=new DateIO().strToTimestamp(new Date()); } //String 转换为 Date public Date strToDate(String strdate){ DateFormat format = new SimpleDateFormat("yyyy-MM-dd");  Date date = null;    try { date = format.parse(strdate); } catch (ParseException e) { e.printStackTrace(); } System.out.println("date:"+date); return date; } //Date 转换为 String public String dateToStr(Date date){ //年月日****-**-** DateFormat format = new SimpleDateFormat("yyyy-MM-dd");  String str = format.format(date);    System.out.println("str:"+str); //年月日**-*-* format = DateFormat.getDateInstance(DateFormat.SHORT);      str = format.format(date);   System.out.println(str);  //年月日****-*-* format = DateFormat.getDateInstance(DateFormat.MEDIUM);      str = format.format(date);  System.out.println(str);  //****年*月*日星期* format = DateFormat.getDateInstance(DateFormat.FULL);      str = format.format(date); System.out.println(str);  return str; } //Timestamp转换为String public String timestampToStr(Long timestamp){ SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//定义格式，不显示毫秒  String str = df.format(timestamp);  System.out.println(str);  return str; } //Date转换为Timestamp public Timestamp strToTimestamp(Date date){ SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");  String time = df.format(date);  Timestamp ts = Timestamp.valueOf(time);  System.out.println(ts);  return ts; } }