void setAssociationTrusted(Collection<JID> associationTrusted) {
        this.associationTrusted = associationTrusted;
    }
Sets the users that are allowed to associate leaf nodes with this collection node.
This collection is going to be used only when the associationPolicy is {@code whitelist}.

@param associationTrusted the users that are allowed to associate leaf nodes with this
       collection node.
xmppserver/src/main/java/org/jivesoftware/openfire/pubsub/CollectionNode.java