public boolean containsIdentity(String category, String type) {
        return identities.contains(category + "/" + type);
    }
Determines whether or not a given identity is included in these entity
capabilities.

@param category the category of the identity
@param type the type of the identity
@return true if identity is included, false if not
xmppserver/src/main/java/org/jivesoftware/openfire/entitycaps/EntityCapabilities.java