Returns the {@code Session} to use when building the {@code Subject} instance. Note that it is more
common to specify a {@link #setSessionId sessionId} to acquire the desired session rather than having to
construct a {@code Session} to be returned by this method.
@return the {@code Session} to use when building the {@code Subject} instance.
Returns the {@code Session} to use when building the {@code Subject} instance. Note that it is more common to specify a {@link #setSessionId sessionId} to acquire the desired session rather than having to construct a {@code Session} to be returned by this method.
@return the {@code Session} to use when building the {@code Subject} instance.