深入理解Logback additivity：禁用控制台默认输出的编程实践

import ch.qos.logback.classic.Level;
import ch.qos.logback.classic.Logger;
import ch.qos.logback.classic.LoggerContext;
import ch.qos.logback.classic.encoder.PatternLayoutEncoder;
import ch.qos.logback.core.rolling.RollingFileAppender;
import ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy;
import ch.qos.logback.core.spi.ContextAwareBase;
import ch.qos.logback.core.util.FileSize;
import org.slf4j.LoggerFactory;

public class LogbackFileOnlyConfigurator {

    private String logFilePath = "logs/application.log";
    private Level logLevel = Level.INFO;
    private LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();

    /**
     * 初始化并配置指定名称的Logger。
     *
     * @param logName 要配置的Logger名称。
     */
    public void initializeLogging(final String logName) {
        // 获取Logger实例
        final Logger logger = loggerContext.getLogger(logName);
        logger.setLevel(this.logLevel);

        // 核心步骤：禁用Logger的additivity特性
        // 这将阻止日志事件传递给父Logger，从而避免默认的控制台输出
        logger.setAdditive(false);

        // 设置文件日志Appender
        setupFileLogging(logger);

        // 示例日志输出
        logger.info("This is an INFO message, should only go to file.");
        logger.debug("This is a DEBUG message (if level permits), should only go to file.");
        logger.warn("A warning message, also to file only.");
    }

    /**
     * 配置一个滚动文件Appender。
     *
     * @param logger 目标Logger。
     */
    private void setupFileLogging(final Logger logger) {
        // 创建RollingFileAppender
        RollingFileAppender<ch.qos.logback.classic.spi.ILoggingEvent> rollingFileAppender = new RollingFileAppender<>();
        rollingFileAppender.setContext(loggerContext); // 必须设置context
        rollingFileAppender.setName("FILE-" + logger.getName()); // 为Appender命名
        rollingFileAppender.setFile(this.logFilePath);

        // 设置日志编码器
        PatternLayoutEncoder encoder = new PatternLayoutEncoder();
        encoder.setContext(loggerContext);
        encoder.setPattern("%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n");
        encoder.start(); // 启动编码器
        rollingFileAppender.setEncoder(encoder);

        // 设置滚动策略
        SizeAndTimeBasedRollingPolicy<ch.qos.logback.classic.spi.ILoggingEvent> rollingPolicy = new SizeAndTimeBasedRollingPolicy<>();
        rollingPolicy.setContext(loggerContext);
        rollingPolicy.setParent(rollingFileAppender); // 关联到Appender
        rollingPolicy.setFileNamePattern("logs/archive/application-%d{yyyy-MM-dd}.%i.log.gz"); // 归档文件名模式
        rollingPolicy.setMaxFileSize(FileSize.valueOf("10MB")); // 单个文件最大10MB
        rollingPolicy.setMaxHistory(30); // 保留30天历史文件
        rollingPolicy.setTotalSizeCap(FileSize.valueOf("1GB")); // 所有归档文件总大小限制
        rollingPolicy.start(); // 启动滚动策略

        rollingFileAppender.setRollingPolicy(rollingPolicy);
        rollingFileAppender.start(); // 启动Appender

        // 将Appender添加到Logger
        logger.addAppender(rollingFileAppender);
    }

    public static void main(String[] args) {
        LogbackFileOnlyConfigurator configurator = new LogbackFileOnlyConfigurator();
        // 初始化一个名为"com.example.MyApp"的Logger
        configurator.initializeLogging("com.example.MyApp");

        // 如果需要，也可以配置其他Logger，它们同样不会输出到控制台
        Logger anotherLogger = configurator.loggerContext.getLogger("com.example.AnotherModule");
        anotherLogger.setLevel(Level.DEBUG);
        anotherLogger.setAdditive(false); // 同样禁用additivity
        // 为anotherLogger添加一个单独的Appender，或者复用上面的文件Appender
        // anotherLogger.addAppender(configurator.getFileAppenderForLogger(anotherLogger)); // 假设有一个方法可以获取或创建Appender

        anotherLogger.info("This is a message from another module, also file only.");
        anotherLogger.debug("This is a debug message from another module.");

        // 关闭LoggerContext以确保所有Appender正确关闭
        ((LoggerContext) LoggerFactory.getILoggerFactory()).stop();
    }
}