log4cxx:使用参数配置追加器 [英] log4cxx: configuring appender with arguments

问题描述

log4cxx的配置通过以下方式从后续xml中读取:

log4cxx's config is read from follow-by xml via:

DOMConfigurator::configure("log4cxx.xml");

但是，要在运行时设置文件名，这会产生一个问题，即要读取多个.xml或在运行中(无论在何处，在内存/磁盘中)创建一个.xml.

But, want to have filename set at runtime, and this creates a problem of either having multiple .xmls for reading, or creating one on the fly (in memory/at disk -- no matter where).

  <appender name="appxNormalAppender" class="org.apache.log4j.FileAppender">
    <param name="file" value="appxLogFile.log" />
    <param name="append" value="true" />
    <layout class="org.apache.log4j.PatternLayout">
      <param name="ConversionPattern" value="%d %-5p [%t:%x] %C{2} (%F:%L) - %m%n" />
    </layout>
  </appender>

是否可以通过任何方法将一些值传递给配置器以替换为<param file="file" value="%%value%%" />或在配置和更改后访问属性?

Is there any way to pass configurator some values to substitute into <param file="file" value="%%value%%" /> or to access the property after configuring and change it?

P.S.这样做的原因:同一程序的多个副本正在写入同一日志，从而使其看起来很奇怪.如何以传统方式使用log4j/log4cxx避免这种情况，而又不发明过多的自行车?

P.S. The reason for doing this: multiple copies of the same program are writing to same log making it look ..strange. How to avoid this with log4j/log4cxx in traditional way without inventing too much bicycles?

推荐答案

大约2年前这个问题袭击了我；我再也无法访问源代码了，但是或多或少，这就是我所做的:

This problem hit me about 2 years ago; I don't have access to source code anymore, but here's what I did, more or less:

1. 扩展了FileAppender，并在配置文件中使用了它.
2. 在setFile()方法内，我在文件名后附加了进程名和id(如果不使用滚动文件，则可以在setOption()方法中完成此操作.

1. Extended the FileAppender and used it in the config file.
2. Inside the setFile() method I appended process name and id to the file name (you can do it in the setOption() method, if you don't use a rolling file.

我们已经有了一种通过内部ID唯一标识我们的流程及其实例的机制；例如，您可以使用PID，也可以添加全局变量，然后在每个应用程序中使用log4cxx将其设置为唯一值，然后在添加程序的setOption方法中使用它.

We already had a mechanism for uniquely identifying our processes and their instances by our internal id; you could use a PID, for example, or add a global variable and set it in every application using log4cxx to your unique value, then using it in the setOption method of your appender.

另请参阅我的答案:将Log4j CompositeTriggeringPolicy功能与log4CXX一起使用

这篇关于log4cxx:使用参数配置追加器的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！