Section Header
    + name := ABSTRACT_FILE;
    - comment := "Abstract File Management";
Section Inherit
    + parent_entry:ENTRY :=
Section Public
    + cursor:UINTEGER_32;
    - set_cursor n:UINTEGER_32 <-
Update.
    - refresh:BOOLEAN <-
    - is_empty:BOOLEAN <-
        Is collection empty ?
    - this:ENTRY <-
Read.
    - read dest:OBJECT :INTEGER <-
    - read dest:ARRAYED size nb_elt:INTEGER :INTEGER <-
Write.
    - write src:ARRAYED from start:INTEGER size nb_elt:INTEGER :INTEGER <-
Close.
    - close:ENTRY <-
Section ENTRY
    - make e:ENTRY :BOOLEAN <-
    - make_read_only e:ENTRY :BOOLEAN <-