I want to move file descriptor to beginning of the record. I have a class named Record. For example, according to parameter, lets say 4, i want to access beginning of the 4. record. In this way, I think I will use seek method. But i need size of Record. in c language, I can say that go to 

```
f seek(3*(size of(Record)))

```

but in Java, how could not find how to learn my Record size. So how can i do this?