I hate Cern ROOT's cd() paradigm

[JonasKunze]

In StrawL1Algorithm you're using something like following:

getPart(partNo);
getData();

and

loadData(i);
StrawData strawData (m_hitData);

Misleading method name getXXX

Common naming conventions expect getXXX() to be a getter method which returns something. void getXXX() is therefore misleading.

Confusing API design

With your API to access the data fragment i you have to call loadData(i); and know that afterwards the requested data is stored in m_hitData. This is hard for a programmer to understand and needs quite some documentation (only for such a simple method). Instead you should implement something like following:

StrawData strawData = getDataFragment(i);

Performance

In some cases it could be useful to have a separate load and get methods (expensive load with many get calls). In this case the API should look similar to following:

loadData(i);

StrawData strawData = getLoadedDataFragment();

But in our case you only call loadData() once. Even if you'd call it several times it would still not be a performance issue as loadData() is only an inline method without any logic calling other inline methods without any logic down to a getter method which is just returning a pointer.