initialization and would not reflect changes that occur after that
time.
They can be changed by the application by calling
System::setProperty().
I dont know the internal implementation of the apr_()-Functions,
but is it possible that their return values (user name, temporary
directory,
...) change at runtime?
"user.dir", the current user directory, might be modified by chdir.
Any of the environment variables could be changed by putenv. I think
it would be better to keep them retrieved on-demand if there is not a
match in the map of property values.
