public void putAll(Map<? extends String, ?> map) {
        if (!CollectionUtils.isEmpty(map)) {
            ensureCombinedPrincipals().putAll(map);
        }
    }
Default implementation of the {@link PrincipalMap} interface.
<p>
*EXPERIMENTAL for Shiro 1.2 - DO NOT USE YET*

@since 1.2
core/src/main/java/org/apache/shiro/subject/SimplePrincipalMap.java