java 换算时区的问题

[foryouever]

目前通过
SimpleDateFormat("ddMMyy hhmmss").parse(String)
来取得字符串中的日期时间信息，但该信息是0时区的，如何简便地转换成东8区并输出？

[didoleo]

import java.util.*;
public class Now {

public static void main(String[] args){

Calendar cal=Calendar.getInstance(TimeZone.getTimeZone("EST"));
//Calendar cal=Calendar.getInstance(TimeZone.getDefault());
String DATE_FORMAT="yyyy-MM-dd HH:mm:ss";
java.text.SimpleDateFormat sdf=
new java.text.SimpleDateFormat(DATE_FORMAT);
sdf.setTimeZone(TimeZone.getTimeZone("EST"));
//sdf.setTimeZone(TimeZone.getDefault());
System.out.println("Now:"+sdf.format(cal.getTime()));

}
}

[didoleo]

public static Date fromDateString(String dateString, String fromFormat)
{
GregorianCalendar gc = new GregorianCalendar();
SimpleDateFormat df = new SimpleDateFormat(fromFormat);
df.setTimeZone(gc.getTimeZone());
df.setLenient(false);
Date date = df.parse(dateString, new ParsePosition(0));
return date;
}