ProtocolLib 4.5.1

Provides read/write access to the Minecraft protocol

  1. dmulloy2
    Native Minecraft Version:
    Tested Minecraft Versions:
    • 1.8
    • 1.9
    • 1.10
    • 1.11
    • 1.12
    • 1.13
    • 1.14
    • 1.15
    Source Code:
    dmulloy2 and aadnk

    If you're 1.8 through 1.15, use the latest release.
    If you're running 1.7 or below, use the 3.7.0 release.

    Thanks for over 800k downloads everyone!

    If you love ProtocolLib or it has made your life significantly easier, consider donating or leaving a positive review below. It really means a lot!

    Certain tasks are impossible to perform with the standard Bukkit API and may require working with and even modifying Minecraft directly. A common technique is to modify incoming and outgoing packets or to inject custom packets into the stream. This is quite cumbersome to do, however, and most implementations will break as soon as a new version of Minecraft has been released, mostly due to obfuscation.

    ProtocolLib is a library that allows read and write access to the Minecraft protocol. It handles most of the overhead required with reflection and channel injection and provides wrappers to simplify packet modification. It is updated with most Minecraft updates so, ideally, individual plugins don't have to. ProtocolLib often doesn't need to be updated for minor updates, especially if there are few code changes (i.e. the 1.8 security updates)

    Useful Links
    Before reporting a bug:
    • Look for an update for ProtocolLib, there's a good chance your error or bug has already been fixed.
    • Read the stack trace and make sure it's an error with ProtocolLib. ProtocolLib's package is com.comphenix.protocol. If you don't see that anywhere, it's not ProtocolLib.
    • Check the common errors wiki page.
    When reporting a bug:
    • I'd prefer it if you used the issue tracker, but you can also do this in the discussion section. Don't report bugs in the reviews.
    • Provide as much information as possible. Provide your ProtocolLib version and Spigot version.
    • Provide any stack traces or "errors" using pastebin.
    For server operators
    Just download ProtocolLib from the link above. It doesn't do anything on its own, it simply allows other plugins to function.

    For developers
    A somewhat dated tutorial can be found here. A new tutorial is in progress on the wiki.

    There is a lightweight alternative to ProtocolLib called TinyProtocol. It is essentially a mechanism to send and receive raw packets without structure modifiers or wrappers. It can be found here.

    Maven repository
    If you're using Maven, you'll be able to automatically download the jar, JavaDoc and associated sources from the following repository:
      <!-- And so on -->
    Code (Java):
    repositories {
        maven { url "" }

    Then add it as a dependency like so:
      <!-- And so on -->
    Code (Java):
    dependencies {
       compileOnly group: "com.comphenix.protocol", name: "ProtocolLib", version: "4.5.0";
    Developers are required to use the ProtocolLib module as a dependency as of version 4.5.0. ProtocolLib-API was a fun little experiment, but had some unfortunate linkage errors.


    Main administrative command. Supports the following sub-commands:
    • config: Reload the configuration file.
    • check: Check for new versions on BukkitDev.
    • version: Displays the currently running version of ProtocolLib.
    • timings: Toggle measuring the amount of CPU time spent by each plugin.
    • listeners: Display what plugins are using ProtocolLib, and the packet types they are intercepting.
    Logs hex representations of the provided packets to a file or to console
    Syntax: /packetlog <protocol> <sender> <packet> [file/console]
    Accepted packets can be found here.

    All of these commands require the permission protocol.admin.

    A small set of configuration options are available:
    Global section
    Code (YAML):
    auto updater.notify: true #Inform any player with the permission when a new version of ProtocolLib is out.
    : false #Automatically download and install the newest version of ProtocolLib. The installation will take effect when the server restarts.
    auto updater.delay
    : 43200 #The number of seconds between each check for a new update.
    auto updater.last
    : 0 #This simply records the last time (in seconds since 01.01.1970) an update check was performed. Set it to 0 to force a new update check.
    : true #If TRUE, ProtocolLib will publish anonymous usage data to Set it to FALSE to opt-out.
    background compiler
    : true #If TRUE, ProtocolLib will try and improve performance by replacing reflection with compiled code on-the-fly.
    ignore version check
    : None #Force ProtocolLib to start for a specified Minecraft version, even if it is incompatible.
    One of the main goals of this project was to achieve maximum compatibility with different versions of Minecraft. And the end result is quite flexible. Aside from package changes, it should be resilient against future changes. It's likely that I won't have to update ProtocolLib for anything but bug fixes and new features.

    How is this possible? It all comes down to reflection in the end. Essentially, no name is hard coded - every field, method and class is deduced by looking at field types, package names or parameter types. It's remarkably consistent across different versions.

    Example Plugins
    Some well-made plugins that do interesting things with ProtocolLib. Check out their source (if available) for some inspiration.
    DM me if you also use ProtocolLib and want to be on the list

    ProtocolLib collects statistics anonymously through BStats. Participation is completely optional and you can opt-out at any time, although it is really helpful in figuring out what environments the plugin is running in (i.e. versions of Spigot, Java, and ProtocolLib), so I can adjust development accordingly.

    If ProtocolLib has made your life significantly easier or you're feeling particularly generous, consider donating! It's a great way to support the many hours I've spent maintaining this plugin and keeps me motivated. Please don't donate if you can't afford it.


    Huge thanks to those who have donated! :)
    (If I missed you or you want to remain anonymous, shoot me a PM)

    • nathan818 - $1000
    • MineCove - $100
    • joehot200 - $75
    • Techcable - $30
    • VintageDon - $25
    • games647 - $25
    • Photon - $15
    • Ltd-Net - $11
    • CultivateMC - $10
    • Axzial - $10
    • snapsi - $5
    • Aberzhulan - $5
    • Art in the Shade - $5
    Please don't leave bug reports in the reviews section. It's the worst place to get support and I won't respond. Use the issue tracker (after checking the common errors page), where I can actually diagnose and fix your issue.

Recent Updates

  1. ProtocolLib v4.5.1
  2. ProtocolLib v4.5.0
  3. ProtocolLib v4.4.0

Recent Reviews

  1. FatalPacket
    Version: 4.5.1
    Thank you for 3 updates in 2 years
    (and for fixing the catch performance)
  2. skymoon500
    Version: 4.5.1
    Thank you very much for this great API.
  3. MatiPlayer1998
    Version: 4.5.0
    One of the best plugin I have ever encounter. With ProtocolLib I can do almost everything. I just want to say I love programming in Minecraft and doing things with ProtocollLib.

    Thanks for amazing contribution and development of plugin :)
  4. NicholasHogan
    Version: 4.5.0
    ProtocolLib is one of those plugins that I don't really know what it does, but I know it is doing something useful! Keep up the awesome work!!

    Nicholas Hogan
  5. ciolgaming
    Version: 4.5.0
    It's one of the best API I've ever used, the fun is endless, and the impossible becomes possible with this one!
  6. Arwind
    Version: 4.5.0
    [13:29:11] [Server thread/ERROR]: [ProtocolLib] INTERNAL ERROR: Cannot load ProtocolLib.
    If this problem hasn't already been reported, please open a ticket
    at with the following data:
    Stack Trace:
    FieldAccessException: Unable to find a field that matches {modifiers=[required: 0, banned: 0], t[email protected]26d4ab18}. Workaround failed too.
    at com.comphenix.protocol.injector.packet.ProxyPacketInjector.initialize(
    at com.comphenix.protocol.injector.packet.ProxyPacketInjector.<init>(
    at com.comphenix.protocol.injector.packet.PacketInjectorBuilder.buildInjector(
    at com.comphenix.protocol.injector.PacketFilterManager.<init>(
    at com.comphenix.protocol.injector.PacketFilterBuilder.buildInternal(
    at com.comphenix.protocol.ProtocolLib.onLoad(
    at org.bukkit.craftbukkit.v1_15_R1.CraftServer.loadPlugins(
  7. iFabri_
    Version: 4.5.0
    I always use this plugins as i need it for some plugins (for example SkinsRestorer) always works perfectly. 10/10 plugin!
  8. lokka30
    Version: 4.5.0
    In the bucket list for the first plugins I install for every new server. Highly appreciate the developers behind this plugin for their work.
  9. ohgui
    Version: 4.5.0
    >WARNING: An illegal reflective access operation has occurred
    WARNING: Illegal reflective access by$1 (file:/home/*********/spigot_1.14.4/plugins/ProtocolLib.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,
    WARNING: Please consider reporting this to the maintainers of$1
    WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
    WARNING: All illegal access operations will be denied in a future release
  10. sebastian97
    Version: 4.5.0
    For some reason when I have this plugin activated, I cant damage mobs and nobody else can either