GameRule Codec & Serialization
| Topic | Specification |
|---|---|
| Serialization Failure | SavedDataStorage.encodeUnchecked crash during world save |
| Fix Release | 1.8.15 |
| Integer Bounds | min = Integer.MIN_VALUE (or Math.min(Integer.MIN_VALUE, defaultValue)) |
🛠️ The Integer GameRule Codec Fix
In Minecraft 26.2, dynamic GameRules are serialized into level.dat / game_rules.dat via SavedDataStorage.encodeUnchecked. In earlier library versions, integer GameRules registered without explicit minimum bounds caused the GameRule codec to enforce strict positive bounds (min = 0), throwing an IllegalStateException when serializing negative integer values or default thresholds.
The Fix in DynamicGameRuleManager
java
// IntegerBuilder initialization fix in DynamicGameRuleManager
public class IntegerBuilder {
private int min = Integer.MIN_VALUE;
private int max = Integer.MAX_VALUE;
public GameRule<Integer> register() {
int effectiveMin = Math.min(min, defaultValue);
int effectiveMax = Math.max(max, defaultValue);
// Uses Codec.INT.intRange(effectiveMin, effectiveMax) to prevent encodeUnchecked bounds check failure
GameRule<Integer> rule = new GameRule<>(
GameRuleType.INT, defaultValue, Codec.INT.intRange(effectiveMin, effectiveMax),
FeatureFlagSet.of(), category, visitor
);
return Registry.register(BuiltInRegistries.GAME_RULE, Identifier.parse(ruleName), rule);
}
}🔒 NBT Namespace Safety
Always namespace dynamic GameRules with modid:rule_name ([ERR-20260510-002]). Unnamespaced dynamic GameRules fail to serialize cleanly into vanilla level saved data, causing silent data loss upon server restart.