~~REDIRECT>https://docs.fabricmc.net/develop/getting-started/launching-the-game#hotswapping-classes~~

====== Applying changes without restarting Minecraft ======
Restarting Minecraft can take a hefty amount of time. Thankfully, there are tools that allow you to apply some changes while the game is running, also called hotswapping.

===== Reload changed classes =====
In Eclipse or IntelliJ IDEA, run Minecraft in debug mode. To apply changes in code, click the "Build" button in IntelliJ IDEA or save in Eclipse.
Note: this only allows you to change method bodies. If you do any other kind of change, you will have to restart.
However, if you use a special JDK, [[https://dcevm.github.io/|DCEVM]] (up to Java 11), you will be able to do most changes, including adding and removing methods and classes.
For Java 11+ use the [[https://github.com/JetBrains/JetBrainsRuntime|JetBrains Runtime]] and add ''-XX:+AllowEnhancedClassRedefinition'' as a VM option to your run configuration:

{{https://i.imgur.com/SuW9MlV.png}}

===== Reload resources =====

==== Reload assets ====
After you make changes to assets such as textures and block/item models, you can rebuild the project and press ''F3 + T'' to apply changes without restarting Minecraft. More specifically, this is how to reload anything the mod provides as a resource pack.

==== Reload data ====
You can apply any changes made in the ''data/'' directory such as recipes, loot tables and tags by rebuilding the project and then using the in-game command ''/reload''. More specifically, this reloads anything the mod provides as a data pack.

===== Hotswapping Mixins =====

You can also hotswap mixins by using Mixin Java agent. For how to achieve that, see [[https://docs.fabricmc.net/develop/getting-started/launching-the-game#hotswapping-mixins|Fabric Docs page]] and [[mixin_hotswaps]].