JAvaシステム時間の呼び出しとフォーマット変換

JAvaはjava.text  java.util   JAva.langパッケージで検索

import java.util.*;
import java.text.*;
public class Text{

	public static void main(String[] args){
		
		long curtime=System.currentTimeMillis();//       1970-1-1 08：00：00     
		System.out.println(curtime);
		
		Date t=new Date();//      
		System.out.println(t);
		
		SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//        
		System.out.println(sdf.format(t));
		
		Date t1=new Date(1000);// 1970-1-1 00：00：00        
		System.out.println(sdf.format(t1));
		
		Date t2=new Date(curtime-1000);//          
		System.out.println(sdf.format(t2));
		
		String now="2015-1-28 10:22:12";
		try{
			System.out.println(sdf.parse(now));//       Date  
		}catch(Exception e){
			System.out.println(e);
		}
		/*
			1422459183319
			Wed Jan 28 23:33:03 CST 2015
			2015-01-28 23:33:03
			1970-01-01 08:00:01
			2015-01-28 23:33:02
			Wed Jan 28 10:22:12 CST 2015
		*/
	}
}