org.apache.log4j.helpers.LogLog
This class used to output log statements from within the log4j package.
这个类用于从log4j包里面输出日志语句
Log4j components cannot make log4j logging calls. However, it is sometimes useful for the user to learn about what log4j is doing.
Log4j组件里面不能使用log4j访问
You can enable log4j internal logging by defining the log4j.configDebug variable.
你能够通过定义log4j.configDebug变量启动log4j的内部日志。
注意：log4j.configDebug变量已经被废弃，现在使用log4j.debug替换。
All log4j internal debug calls go to System.out where as internal error messages are sent to System.err. All internal messages are prepended with the string "log4j: ".