Validation & Comments

A good configuration file documents itself. YAML Config allows you to add extensive comments and metadata to your entries.

Adding Comments

Comments are added using the .withComments(...) method on any entry object.

builder.defineBoolean("enable_features", true)
       .withComments(
           "Master switch for all features.",
           "If false, the mod does nothing."
       );

Result (YAML):

# Master switch for all features.
# If false, the mod does nothing.
# Default value: true
enable_features: true

Controlling Metadata

By default, YAML Config appends the Default Value and Validation Constraints (like Min/Max) to the comments automatically. You can toggle this.

builder.defineInteger("secret_value", 123)
       .withComments(
           false, // showDefaultValues
           false, // showValidationParameters
           "This is a secret."
       );

In-Game Tooltips

The comments you define here are automatically converted into tooltips in the Configuration GUI. When a user hovers over the text of an entry, they will see your comments, making it easy to understand what the setting does without leaving the game.

Validation Logic

Every IConfigEntry has a validate(T value) method.

• Primitive Entries: Check min/max bounds.
• String Entries: Check length and Regex.
• Registry Entries: Check registry existence.

If validate throws a ConfigEntryValidationException:

1. The error is logged.
2. The value is rejected.
3. The entry reverts to its previous valid state or default.