looking for developper informations about Calc

Hello everybody,
   I'm working in an Eclipse project called Papyrus (https://eclipse.org/papyrus/ ) which needs to 
provide table editor to edit UML models. Currently we are using the NatTable widget 
(https://www.eclipse.org/nattable/ ). This widget is very powerful, but each year our users ask us 
to customize it more in order to look like well known spreadsheets. That's why I just join this 
forum to ask some questions. Here I will give you a list of the main features used in NatTable and 
for which I would like to know if they already exist in Calc and if there is an API (in Java ?) to 
drive them:
- Customize the cell appearance with CSS
- Manage the cell contents
- Manage the cell access (read-only or read-write)
- Declare custom cell editors (or dialogs) on cells to edit their contents
- Show/hide columns or rows (not a deletion)
- Display data as a tree in a column (with expanding, collapsing and hiding intermediate row 
without to hide its children)

In addition, I would like to know if the toolbars and the menus can be customized and hidden easily.
Concerning the cell management, in the NatTable widget we proceed in 2 steps :
-              One step to declare the cell contents : we declare the java object represented by 
the cell. It is not a string at this level, it is a java object, like a list, a Boolean, an 
integer, ...)
-              The second step calls a LabelProvider which returns the text to display for the 
given object

Is it the same kind of process in Calc or it is only a text management ?

So, to resume,  my main question concerns the customization capabilities of Calc to manipulate its 
behavior programmatically.

At the end, please, could you indicate me where I can found developer documentation about Calc and 
its API.

Best Regards,
--
Vincent LORENZO
01-69-08-17-24
CEA Saclay Nano-INNOV
Institut CARNOT CEA LIST
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