private void clearRunAsIdentitiesInternal() {
        //try/catch added for SHIRO-298
        try {
            clearRunAsIdentities();
        } catch (SessionException se) {
            LOGGER.debug("Encountered session exception trying to clear 'runAs' identities during logout.  This "
                    + "can generally safely be ignored.", se);
        }
    }
Returns {@code true} if this Subject is allowed to create sessions, {@code false} otherwise.

@return {@code true} if this Subject is allowed to create sessions, {@code false} otherwise.
@since 1.2
core/src/main/java/org/apache/shiro/subject/support/DelegatingSubject.java