Atlas-C++ - Objects

Last modified: Wed Jun 21 04:24:38 UTC 2000

1. GENERAL NOTES

implement hierarchy as given in atlas spec.
have attributes

2.1 FIRST ITERATION

attributes are message::objects
attributes are stored in a map
attributes can be checked for
attributes can be retrieved
attributes can be stored
attributes can be removed
objects have default attributes (set in constructors)
objects can be converted into Message::Object
objects can be instantiated (i.e. parents = id, objtype is an instance)

2.1.1 INHERITANCE

We use public inheritance
We use virtual functions
In constructors:
  - First we call our parent
  - Then we do our own thing
In GetAttr:
  - No inheritance issues
  - In fact, we can just rely on root's implementation
In SetAttr:
  - No inheritance issues
  - In fact, we can just rely on root's implementation
In RemoveAttr:
  - No inheritance issues
  - In fact, we can just rely on root's implementation

2.2 SECOND ITERATION

attributes can be specific types
attributes can be stored as members
access functions for specific attributes (these can be non-virtual inline)
protected send functions for specific attributes (-"-)
virtual functions need to be overrided

Note: attributes should only be stored once in the hierarchy

2.2.1 VIRTUAL FUNCTIONS

GetAttr:
 - if name == one of the locally stored, return that
 - else call parent

SetAttr:
 - if name == one of the locally stored, set that & return
 - else call parent

HasAttr:
 - if name == on of the locally stored, return true
 - else call parent

RemoveAttr:
 - if name== one of the locally stored, no effect
 - else call parent

SendContents:
 - send each of the locally stored (using the protected functions)
 - call parent

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And that's all there is to it!

Stefanus Du Toit (sdt) -- <sdt@gmx.net>