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====== Reading the Minecraft source ======
Reading the Minecraft source is an important skill in modding. This is mainly because
    * Most of the Minecraft things are not documented
    * Documentations/tutorials get outdated fairly quickly

To read the Minecraft source, you need to generate sources first. See the "Generating Minecraft Sources" section in [[tutorial:setup|Setting up a mod development environment]].

===== Searching for a Minecraft class =====
To search a Minecraft class, follow these steps.

===== Intellij IDEA =====
    - Open the search pane with {{https://i.ibb.co/rmztpCy/IMG-0712.png?height=64}} or {{https://i.ibb.co/2SDypGK/kbs-meta-o.png?height=80}} on mac
    - Set the search scope to ''Project and Libraries'' or wider
    - Type the class name in the search box

===== Visual Studio Code =====
    - Open the search pane with ''Ctrl + P''
    - Type the class name with prefix ''#''

===== Eclipse =====
    - Open the search pane with ''Ctrl + Shift + T''

In Visual Studio Code, you can also use ''Ctrl + T'' to open the class search directly.

===== Finding the class you want to see ====
Locating the part of code you want to see is a challenging task. Here are some tips.

    * Take full advantage of IDE's ability to find the relevant code such as ''Call hierarchy'', ''Method hierarchy'' or ''Type hierarchy''.
    * Take a look at open source mods which are similar to what you want to make.
    * If you are adding a new content, there is a good chance you need to access registries defined in ''net.minecraft.util.registry.Registries''.
    * Keep in mind that everything starts from one main class (''net.minecraft.client.main.Main'' for client, ''net.minecraft.server.Main'' for dedicated server).
    * Search Minecraft code for translation keys. ''assets/assets/minecraft/lang/en_us.json'' contains all keys used in vanilla.

===== Reading the bytecode =====
Reading the bytecode is occasionally required because
    * Mixin operates on bytecode, not the source code. Understanding the bytecode is essential when you write a complex mixin.
    * Decompiler (FernFlower) is not perfect. It sometimes produces an invalid java code such as ''int i = true;''.

If you are not familiar with the java bytecode, reference [[https://docs.oracle.com/javase/specs/jvms/se17/html/jvms-6.html|the JVM specification]].

To see the bytecode, follow these steps.

==== Intellij IDEA ====
    - Open the class of which you want to see the bytecode
    - Select ''View'' from the main menu
    - Select ''Show Bytecode''

==== External Tools ====
If your IDE doesn't support bytecode viewing, use external bytecode viewers such as https://github.com/Konloch/bytecode-viewer.

===== FAQ =====
**Where are the generated sources?**

It's either in the user gradle cache (''~/.gradle/caches/fabric-loom'') or in the project gradle cache (''./.gradle/loom-cache'').
You can use the sources jar outside of your IDE.