⚡ Java Logger

A modern, color‑enabled and extensible Java logger focused on clarity, performance, and seamless integration with external log systems.

---

🚀 Features

• 🧵 Thread‑safe asynchronous logging
  Log calls never block your application — messages are queued and processed in a background worker.

• ⚡ Non‑blocking write pipeline
  Ideal for high‑performance servers, tools, and microservices.

• 🎨 ANSI color support
  Clean, readable console output with colored log levels.

• 📁 latest.log session file
  All logs of the current runtime are written into a single session file.

• 📅 Automatic daily rotation
  On shutdown, latest.log is appended to YYYY‑MM‑DD.log automatically.

• 🔌 External log uplinks via Configuration.activeConsumer
  Forward logs to WebSockets, databases, dashboards, or fully override local logging.

• 🎚️ Configurable log levels via Configuration.minimumLevel
  Control which log levels are active (useful for dev/production switching).

• 📦 Zero dependencies
  Pure Java — no external libraries required.

---

📦 Maven‑Integration

<dependency>
    <groupId>de.juniorjacki.utils</groupId>
    <artifactId>logger</artifactId>
    <version>0.1.2</version>
</dependency>

🛠️ Usage

Enable the logger

import de.juniorjacki.utils.logger.FileWriter;
import de.juniorjacki.utils.logger.Logger;

public class Main {
    public static void main(String[] args) throws Exception {
        FileWriter.enable("logs"); // Enables Saving of Logs into the "logs" folder

        Logger.info("Server started");
        Logger.warn("Latency increased to",50,"ms");
        Logger.error("Failed to load resource",new Exception("Loading Error"));
    }
}

Output

2026-04-28 20:31:12.123 [INFO] Main.main: Server started
2026-04-28 20:31:12.124 [WARN] Main.main: Latency increased to 50 ms
2026-04-28 20:31:12.125 [ERROR] Main.main: Failed to load resource
java.lang.Exception: Loading Error
    at Main.main(Main.java:8)

📅 Automatic Rotation

When the program exits:

• latest.log is automatically appended to the daily file (YYYY‑MM‑DD.log)
• No manual action required

🔌 External Log Integration (Log Uplink)

The logger supports forwarding all logs to external systems:

Example: Send logs to a WebSocket uplink

Configuration.activeConsumer = (timestamp,source, level, message) -> {
    MyWebSocketClient.send(
        "[" + level + "] " + source + ": " + message
    );
    return false; // keep local output active
};

Example: Fully override local logging

Configuration.activeConsumer = (timestamp,source, level, message) -> {
    ExternalLogUplink.push(level, source, message,timestamp);
    return true; // suppress local output
};

Example: Write logs into a database

Configuration.activeConsumer = (timestamp,source, level, message) -> {
    Database.insertLog(level.name(), source, message,timestamp);
    return false; // keep local output active
};

Behaviour

Return value	Meaning
true	Local output is suppressed
false	Local output remains active

🎚️ Log Level Configuration

The logger allows you to control which log levels are processed (Useful for Dev/Production Switching) using:

Configuration.minimumLevel

Log levels are ordered exactly as defined in the enum:

public enum Level {
    DEBUG,
    WARNING,
    ERROR,
    INFO
}

The logger activates all levels whose ordinal is greater than or equal to the selected one.

✔ Default behavior

Configuration.minimumLevel = Level.DEBUG;

This enables all log levels.