記錄級別

Java Logging Api 有 7 個級別 。降序的級別為：

• SEVERE（最高價值）
• WARNING
• INFO
• CONFIG
• FINE
• FINER
• FINEST（最低價值）

預設級別為 INFO（但這取決於系統並使用虛擬機器）。

注意 ：還有 OFF（可用於關閉登出）和 ALL（OFF 的對位）。

程式碼示例：

import java.util.logging.Logger;

public class Levels {
    private static final Logger logger = Logger.getLogger(Levels.class.getName());

    public static void main(String[] args) {

        logger.severe("Message logged by SEVERE");
        logger.warning("Message logged by WARNING");
        logger.info("Message logged by INFO");
        logger.config("Message logged by CONFIG");
        logger.fine("Message logged by FINE");
        logger.finer("Message logged by FINER");
        logger.finest("Message logged by FINEST");

        // All of above methods are really just shortcut for
        // public void log(Level level, String msg):
        logger.log(Level.FINEST, "Message logged by FINEST");
    }
}

預設情況下，執行此類將僅輸出級別高於 CONFIG 的訊息：

Jul 23, 2016 9:16:11 PM LevelsExample main
SEVERE: Message logged by SEVERE
Jul 23, 2016 9:16:11 PM LevelsExample main
WARNING: Message logged by WARNING
Jul 23, 2016 9:16:11 PM LevelsExample main
INFO: Message logged by INFO