Java 使用ConfigurationFactory以编程方式配置log4j2

我试图仅通过使用和引用来配置和设置Log4j2。我使用的代码如下所示：

public class LoggingConfiguration {

    public static final String PATTERN_LAYOUT = "[%d] [%t] [%-5level] - %msg (%logger{1}:%L) %n%throwable";
    public static final String LOG_FILE_NAME = "app.log";
    public static final String LOG_FILE_NAME_PATTERN = LOG_FILE_NAME + "-yyyy.MM.dd";

    static {
        ConfigurationFactory.setConfigurationFactory(new Log4j2ConfigurationFactory());
    }

    /**
     * Just to make JVM visit this class to initialize the static parts.
     */
    public static void configure() {
    }

    @Plugin(category = "ConfigurationFactory", name = "Log4j2ConfigurationFactory")
    @Order(0)
    public static class Log4j2ConfigurationFactory extends ConfigurationFactory {

        @Override
        protected String[] getSupportedTypes() {
            return null;
        }

        @Override
        public Configuration getConfiguration(ConfigurationSource source) {
            return new Log4j2Configuration();
        }

        @Override
        public Configuration getConfiguration(String name, URI configLocation) {
            return new Log4j2Configuration();
        }

    }

    private static class Log4j2Configuration extends DefaultConfiguration {

        public Log4j2Configuration() {
            setName("app-log4j2");
            String root = System.getProperty("APP_ROOT", "/tmp");
            if (!root.endsWith("/")) {
                root += "/";
            }
                            // MARKER
            Layout<? extends Serializable> layout = PatternLayout.createLayout(PATTERN_LAYOUT, null, null, null, null);

            String oneDay = TimeUnit.DAYS.toMillis(1) + "";
            String oneMB = (1024 * 1024) + "";
            final TimeBasedTriggeringPolicy timeBasedTriggeringPolicy = TimeBasedTriggeringPolicy.createPolicy(oneDay,
                    "true");
            final SizeBasedTriggeringPolicy sizeBasedTriggeringPolicy = SizeBasedTriggeringPolicy.createPolicy(oneMB);
            final CompositeTriggeringPolicy policy = CompositeTriggeringPolicy.createPolicy(timeBasedTriggeringPolicy,
                    sizeBasedTriggeringPolicy);
            final DefaultRolloverStrategy strategy = DefaultRolloverStrategy.createStrategy("7", "1", null,
                    Deflater.DEFAULT_COMPRESSION + "", this);
            Appender appender = RollingFileAppender.createAppender(root + LOG_FILE_NAME, LOG_FILE_NAME_PATTERN, "true",
                    "app-log-file-appender", "true", "true", policy, strategy, layout, null, null, null, null, null);
            addAppender(appender);
            getRootLogger().addAppender(appender, Level.INFO, null);
        }
    }

}

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如果我在上面的代码中注释掉

MARKER

之后的代码，它会起作用，但似乎缺少配置滚动文件追加器的功能。我应该怎么做才能解决这个问题？

在log4j 2.x中，您必须以这种方式指定日期格式

public static final String LOG_FILE_NAME_PATTERN = LOG_FILE_NAME + "-%d{dd-MM-yyy}";

• %

  标记格式的开头

• d

  表示它是一种日期格式（您也可以使用

  date

  ）
• 在花括号

  {}

  中定义格式化程序的选项。在本例中为日期格式。你可以使用a可以接受的任何东西

此外，您还可以使用：

• %d{ABSOLUTE}

  ->

  HH:mm:ss，SSS

• %d{COMPACT}

  ->

  yyyymmddhhmmssss

• %d{DATE}

  ->

  dd-MMM-yyyy-HH:mm:ss，SSS

• %d{ISO8601_BASIC}

  ->

  yyyyMMdd HHmmss，SSS

• %d{ISO8601}

  ->

  yyyy-MM-dd-HH:MM:ss，SSS

---

注：此信息基于log4j 2.0-beta9（当前版本）。由于它是beta版，所以可能会略有变化。

如何初始化此log4j2实例？我的意思是无论是在主课还是其他地方？你能告诉我你采取的方法吗

public static final String LOG_FILE_NAME_PATTERN = LOG_FILE_NAME + "-%d{dd-MM-yyy}";