JAVA取得システム時間

import java.util.*;    
  
public class D    
{    
public static void main(String []abc)    
{    
    int y,m,d,h,mi,s;    
    Calendar cal=Calendar.getInstance();    
    y=cal.get(Calendar.YEAR);    
    m=cal.get(Calendar.MONTH);    
    d=cal.get(Calendar.DATE);    
    h=cal.get(Calendar.HOUR_OF_DAY);    
    mi=cal.get(Calendar.MINUTE);    
    s=cal.get(Calendar.SECOND);    
    System.out.println("     "+y+" "+m+" "+d+" "+h+" "+mi+" "+s+" ");    
}    
  
}   
##########################################################################    
public class Main{    
    public static void main(String[] args){    
        java.util.Calendar c=java.util.Calendar.getInstance();    
        java.text.SimpleDateFormat f=new java.text.SimpleDateFormat("yyyy MM dd hh mm ss ");    
        System.out.println(f.format(c.getTime()));    
    }    
}  
 
 
##########################################################################   
 
public String GetNowDate(){   
    String temp_str="";   
    Date dt = new Date();   
    //   aa  “  ” “  ”    HH  24           hh  12      
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss aa");   
    temp_str=sdf.format(dt);   
    return temp_str;   
}
}

SimpleDateFormat dateformat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateStr = dateformat.format(System.currentTimeMillis());

SimpleDateFormat dateformat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
try {
    long time = dateformat.parse("2016-09-02 23:02:17").getTime();
    System.out.println(time);
} catch (ParseException e) {
    e.printStackTrace();
}