The source code for Locks, a small, but unique Minecraft mod that introduces flexible and universal locks which can be dynamically attached to multiple blocks of any kind, including other mods, a fun lock picking mechanic as well as lots of other little, but useful tools and utilities.
CurseForge: https://minecraft.curseforge.com/projects/locks
Minecraft Forum: https://www.minecraftforum.net/forums/mapping-and-modding-java-edition/minecraft-mods/2759819-locks-v2-0-dynamic-locking-system-lock-picking