public User loadUser(UUID uniqueId, String username) {
        final long startTime = System.currentTimeMillis();

        // register with the housekeeper to avoid accidental unloads
        this.plugin.getUserManager().getHouseKeeper().registerUsage(uniqueId);

        // save uuid data.
        PlayerSaveResult saveResult = this.plugin.getStorage().savePlayerData(uniqueId, username).join();

        // fire UserFirstLogin event
        if (saveResult.includes(PlayerSaveResult.Outcome.CLEAN_INSERT)) {
            this.plugin.getEventDispatcher().dispatchUserFirstLogin(uniqueId, username);
        }

        // most likely because ip forwarding is not setup correctly
        // print a warning to the console
        if (saveResult.includes(PlayerSaveResult.Outcome.OTHER_UNIQUE_IDS_PRESENT_FOR_USERNAME)) {
            Set<UUID> otherUuids = saveResult.getOtherUniqueIds();

            this.plugin.getLogger().warn("LuckPerms already has data for player '" + username + "' - but this data is stored under a different UUID.");
            this.plugin.getLogger().warn("'" + username + "' has previously used the unique ids " + otherUuids + " but is now connecting with '" + uniqueId + "'");

            if (uniqueId.version() == 4) {
                if (this.plugin.getBootstrap().getType() == Platform.Type.BUNGEECORD) {
                    this.plugin.getLogger().warn("The UUID the player is connecting with now is Mojang-assigned (type 4). This implies that BungeeCord's IP-Forwarding has not been setup correctly on one (or more) of the backend servers.");
                } if (this.plugin.getBootstrap().getType() == Platform.Type.VELOCITY) {
                    this.plugin.getLogger().warn("The UUID the player is connecting with now is Mojang-assigned (type 4). This implies that Velocity's IP-Forwarding has not been setup correctly on one (or more) of the backend servers.");
                } else {
                    this.plugin.getLogger().warn("The UUID the player is connecting with now is Mojang-assigned (type 4). This implies that one of the other servers in your network is not authenticating correctly.");
                    this.plugin.getLogger().warn("If you're using BungeeCord/Velocity, please ensure that IP-Forwarding is setup correctly on all of your backend servers!");
                }
            } else {
                this.plugin.getLogger().warn("The UUID the player is connecting with now is NOT Mojang-assigned (type " + uniqueId.version() + "). This implies that THIS server is not authenticating correctly, but one (or more) of the other servers/proxies in the network are.");
                this.plugin.getLogger().warn("If you're using BungeeCord/Velocity, please ensure that IP-Forwarding is setup correctly on all of your backend servers!");
            }

            this.plugin.getLogger().warn("See here for more info: https://luckperms.net/wiki/Network-Installation#pre-setup");
        }

        User user = this.plugin.getStorage().loadUser(uniqueId, username).join();
        if (user == null) {
            throw new NullPointerException("User is null");
        }

        final long time = System.currentTimeMillis() - startTime;
        if (time >= 1000) {
            this.plugin.getLogger().warn("Processing login for " + username + " took " + time + "ms.");
        }

        return user;
    }
Gets the unique players which have connected to the server since it started.

@return the unique connections
common/src/main/java/me/lucko/luckperms/common/plugin/util/AbstractConnectionListener.java