如何为 log4j2 RollingFileAppender 进行编程配置

Question

我在没有配置文件的情况下以编程方式使用 log4j2，而是在代码中配置它。我正在尝试使用 log4j2 RollingFileAppender 来保存最后 10 个日志文件。我尝试使用SizeBasedTriggeringPolicy 限制文件大小。大小限制有效，但它不会创建旧的日志文件，只会继续删除并写入一个原始日志文件。

public static void configLog() {
        String dir = System.getProperty("java.io.tmpdir") + "test\\";
        final LoggerContext ctx = (LoggerContext) LogManager.getContext(false);
        final Configuration config = ctx.getConfiguration();
        PatternLayout layout = PatternLayout.newBuilder().withConfiguration(config).withPattern(PatternLayout.SIMPLE_CONVERSION_PATTERN).build();
        SizeBasedTriggeringPolicy policy = SizeBasedTriggeringPolicy.createPolicy("1KB");
        DefaultRolloverStrategy strategy = DefaultRolloverStrategy.createStrategy("10", "0", null, null, config);
        RollingFileManager fileManager = RollingFileManager.getFileManager(dir + "log\\test.log", dir + "log\\test-%i.log", false, false, policy, strategy, null, layout, 128);
        policy.initialize(fileManager);
        RollingFileAppender appender = RollingFileAppender.createAppender(dir + "log\\test.log", dir + "log\\test-%i.log",
                "false", "File", "false", "128", "true", policy, strategy, layout, (Filter) null, "false", "false", (String) null, config);
        appender.start();
        config.addAppender(appender);
        AppenderRef ref = AppenderRef.createAppenderRef("File", Level.INFO, null);
        AppenderRef[] refs = new AppenderRef[] { ref };
        LoggerConfig loggerConfig = LoggerConfig.createLogger("true", Level.INFO, LogManager.ROOT_LOGGER_NAME, "true",
                refs, null, config, null);
        loggerConfig.addAppender(appender, Level.INFO, null);
        config.addLogger(LogManager.ROOT_LOGGER_NAME, loggerConfig);
        ctx.updateLoggers();
    }

我没有找到很多使用 java 配置日志记录的示例，但我的应用程序需要这样做。我取大部分代码的例子在这里http://logging.apache.org/log4j/2.x/manual/customconfig.html（第二个代码部分）。

为什么不创建/保存旧的日志文件？

Answer 1

尽管这是一个老问题，其他人可能会觉得它很有用，但我相信这是因为

RollingFileAppender.createAppender(dir + "log\\test.log", dir + "log\\test-%i.log",
            "false", "File", "false", "128", "true", policy, strategy, layout, (Filter) null, "false", "false", (String) null, config);

应该是

RollingFileAppender.createAppender(dir + "log\\test.log", dir + "log\\test-%i.log",
            "true", "File", "false", "128", "true", policy, strategy, layout, (Filter) null, "false", "false", (String) null, config);

第三个参数是附加选项 https://logging.apache.org/log4j/2.x/log4j-core/apidocs/org/apache/logging/log4j/core/appender/RollingFileAppender.html