java.util.date时间类常用代码整理

import java.util.Date;
import java.text.SimpleDateFormat;
 
public class  {
   public static void main(String[] args) { 
      SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
      System.out.println(df.format(new Date()));// new Date()为获取当前系统时间
   }
}

Date date = new Date();
Timestamp timestamp = new Timestamp(date.getTime());

String str = "2013-01-14"; 
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); 
Date date = null; //初始化date 
try {  
	date = sdf.parse(str); //Mon Jan 14 00:00:00 CST 2013 
} catch (ParseException e) { 
	e.printStackTrace(); 
}

String str = "2013-01-14"; 
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); 
java.sql.Date sdate = null; //初始化 
try { 
 	java.util.Date udate = sdf.parse(str); 
	sdate = new java.sql.Date(udate.getTime()); //2013-01-14 
} catch (ParseException e) {
	e.printStackTrace(); 
}

public String TimeStamp2Date(String timestampString, String formats){  
	Long timestamp = Long.parseLong(timestampString)*1000;  
  	String date = new java.text.SimpleDateFormat(formats).format(new java.util.Date(timestamp));  
  	return date;  
}

SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date date=null;
try {
	date = sdf.parse("2012-07-25 21:00:00");
} catch (ParseException e) {
	e.printStackTrace();
}
Calendar ca=Calendar.getInstance();
ca.setTime(date);
ca.add(Calendar.HOUR_OF_DAY, 3);
System.out.println(sdf.format(ca.getTime()));