String time = "1351504294";
long t = Long.parseLong(time);
Timestamp ts = new Timestamp(t*1000);

Timestamp ts = new Timestamp(t*1000);
String s = ts.toString().split('\.')[0];

Timestamp ts = new Timestamp(t*1000);
String s = new SimpleDateFormat("MM/dd/yyyy-mm-dd hh:mm:ss").format(ts);

public class Time {

    public static void main(String[] args){

        String time = "1351504294";
        long t = Long.parseLong(time);
        Timestamp ts = new Timestamp(t*1000);

        String date = new SimpleDateFormat("YYYY-MM-dd hh:mm:ss").format(ts);
        System.out.println(date);
    }
}