Logging

Every mod has access to a built-in logger via getLogger(). Hytale uses Google Flogger for logging.

Basic Usage

import java.util.logging.Level;

// in your mod class
getLogger().atInfo().log("Server started");
getLogger().atWarning().log("Something might be wrong");
getLogger().atSevere().log("Critical error occurred");
getLogger().at(Level.FINE).log("Debug info");  // explicit level syntax

Log Levels

Level	Use For
Level.SEVERE	Errors and failures
Level.WARNING	Potential problems
Level.INFO	General information
Level.CONFIG	Configuration and setup messages
Level.FINE	Debug information (hidden by default)
Level.FINER	Detailed debug (hidden by default)
Level.FINEST	Trace-level debug (hidden by default)

Convenience methods: atSevere(), atWarning(), atInfo(), atConfig(), atFine(), atFiner(), atFinest().

Formatting

Use %s placeholders for formatting (printf-style):

String playerName = "Steve";
int count = 42;

getLogger().atInfo().log("Player %s joined", playerName);
getLogger().atInfo().log("Loaded %d items", count);
getLogger().atInfo().log("Player %s has %d coins", playerName, count);

Logging Exceptions

Use withCause() to attach an exception:

try {
    loadConfig();
} catch (Exception e) {
    getLogger().atSevere().withCause(e).log("Failed to load configuration");
}

This logs both the message and the full stack trace.

Rate Limiting

Avoid log spam with built-in rate limiting:

import java.util.concurrent.TimeUnit;

// log only every 100th occurrence
getLogger().atWarning().every(100).log("Frequent event occurred");

// log at most once every 5 seconds
getLogger().atWarning().atMostEvery(5, TimeUnit.SECONDS).log("Rate-limited message");

Stack Traces

Include a stack trace for debugging (without an exception):

import com.google.common.flogger.StackSize;

getLogger().atWarning().withStackTrace(StackSize.MEDIUM).log("How did we get here?");

Stack sizes: SMALL (10 frames), MEDIUM (20), LARGE (50), FULL (all).

Conditional Logging

For expensive operations, check if the level is enabled first:

if (getLogger().at(Level.FINE).isEnabled()) {
    String expensiveDebugInfo = computeDebugState();
    getLogger().at(Level.FINE).log("Debug state: %s", expensiveDebugInfo);
}

Changing Log Level at Runtime

Enable debug logging dynamically:

getLogger().setLevel(Level.FINE);  // enable FINE and above
getLogger().setLevel(Level.INFO);  // back to normal

Static Logger Access

For utility classes without mod context, use HytaleLogger:

import com.hypixel.hytale.logger.HytaleLogger;

// per-class logger (recommended)
private static final HytaleLogger LOGGER = HytaleLogger.forEnclosingClass();

LOGGER.atInfo().log("Processing data");

// sub-logger for subsystems
HytaleLogger dbLogger = LOGGER.getSubLogger("database");
dbLogger.atInfo().log("Connected");  // logged as "[MyClass][database]"

// global logger
HytaleLogger.getLogger().atWarning().log("Something happened");