Date date = new Date();
        
long stamp = date.getTime()/1000;
        
System.out.println(stamp);

long timestamp = System.currentTimeMillis()/1000;
        
System.out.println(timestamp);

Date date = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").parse("2020-03-25 15:01:17");
        
long timestamp = date.getTime()/1000;
        
System.out.println(timestamp);