Purpose of the Plugin.initApplication(InnerApplication) method

Question

Hi,
Does anybody know what is the purpose of the above method? When and where shall it be called?
As far as I know the xlet hasn't access to the plugin, so it cannot call it. There remains only a terminal.
On other hand the terminal:
1) if it supports the InnerApplication (ex. HTMLInnerApplication) then it doesn't need this method
2) if it doesn't support any InnerApplication then it cannot create any instance of the InnerApplication which could be send to the above method as the parameter
The only thing that comes to mind is to use this method in the implementation of the InnerApplicationContainer::InnerApplicationContainer(InnerApplication) constructor. But this causes other problems:
1) the terminal doesn't know anything about the application id or other application attributes, which should be later accessible through the method XletContext.getXletProperty by this inner application
2) the terminal doesn't know which plugin shall be used to create the xlet
a) there is one exception if the InnerApplicationContainer::InnerApplicationContainer(InnerApplication) constructor is invoked by the delegated application, the terminal could assume that it is the same plugin which was used to create this delegated application
b) but what if it is not a delegated application? Shall the constructor throw some exception?
Thanks in advance,
Adam L.

Answer 1

Static methods are often used for the implementation of utility methods. Please have a look at the class CL_ABAP_CHAR_UTILITIES for example.
You use the methods of this class in the same way as you would use a function in ABAP (like
LINES( itab )
). You use it in a static way because the functionality is always the same no matter in what context you are calling the function.
The purpose of instance methods is that their logic is in some way related to an attribute of the object instance that you use to call it.
For example, you create an instance of object PO (a purchase order) called MY_PO. Then the method
MY_PO->ADD_POSITION
would add a position to a concrete PO that has a unique number etc. But if the object has a static method DELETE_POSITION then it just deletes the current position of a PO, regardless on which concrete PO you are acting at the moment.
I hope this clarifies it for you.
Regards,
Mark