//时间戳转化为Sting或Date 
  SimpleDateFormat format = newSimpleDateFormat("yyyy-MM-dd HH:mm:ss"); 
  Long time=newLong(445555555); 
  String d = format.format(time); 
  Date date=format.parse(d); 
  System.out.println("Format To String(Date):"+d); 
  System.out.println("Format To Date:"+date); 
  运行结果：
    Format To String(Date):1970-01-06 11:45:55
Format To Date:Tue Jan 06 11:45:55 CST 1970

//Date或者String转化为时间戳 
  SimpleDateFormat format = newSimpleDateFormat("yyyy-MM-dd HH:mm:ss"); 
  String time="1970-01-06 11:45:55"; 
  Date date = format.parse(time); 
  System.out.print("Format To times:"+date.getTime());

 //Date或者String转化为时间戳 
   SimpleDateFormat format = newSimpleDateFormat(" yyyy-MM-dd HH:mm:ss "); 
   String time="1970-01-06 11:45:55"; 
   Date date = format.parse(time); 
   System.out.print("Format To times:"+date.getTime()); 

 //Date或者String转化为时间戳
SimpleDateFormat format = newSimpleDateFormat(" yyyy-MM-dd HH:mm:ss "); 
String time=" 1970-01-06 11:45:55 ";//注：改正后这里前后也加了空格 
Date date = format.parse(time); 
System.out.print("Format To times:"+date.getTime()); 
 运行结果：
  Format To times:445555000

import java.text.ParseException; 
import java.text.SimpleDateFormat; 
import java.util.Date; 
 
public class Baidu { 
 
/** 
* @param args 
*/ 
public static void main(String[] args) { 
try { 
String time = "2011/07/29 14:50:11"; 
Date date = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss").parse(time); 
long unixTimestamp = date.getTime()/1000; 
System.out.println(unixTimestamp); 
} catch (ParseException e) { 
e.printStackTrace(); 
} 
} 
}