热门面试题与答案和在线测试
面向面试准备、在线测试、教程与实战练习的学习平台

通过聚焦学习路径、模拟测试和面试实战内容持续提升技能。

WithoutBook 将分主题面试题、在线练习测试、教程和对比指南整合到一个响应式学习空间中。

面试准备

模拟考试

设为首页

收藏此页面

订阅邮箱地址
首页 / 面试主题 / Log4j
WithoutBook LIVE 模拟面试 Log4j 相关面试主题: 39

面试题与答案

了解热门 Log4j 面试题与答案,帮助应届生和有经验的候选人为求职面试做好准备。

共 35 道题 面试题与答案

面试前建议观看的最佳 LIVE 模拟面试

了解热门 Log4j 面试题与答案,帮助应届生和有经验的候选人为求职面试做好准备。

面试题与答案

搜索问题以查看答案。

资深 / 专家级别面试题与答案

问题 1

How do you define logging for your application?

To define logging for your application, you have to download the log4j framework (log4j.jar) from the apache site.
Once log4j jars are downloaded, make sure that these jars are in classpath of your application. lets say you have web-application need to be added log4j. In this case, log4j jars are copied to WEB-INF/lib folder of your web application.
create new file either logging.properties or log4j.xml which will be copied to WEB-INF/classes folder.
logging.properties/log4j.xml contains the all the configuration related to logging mechanism and logger level and package that you want to define logger level.

Example:
logging.properties:
logger.level=INFO
logger.handlers=CONSOLE,FILE,RejRec
handler.RejRec=org.jboss.logmanager.handlers.PeriodicRotatingFileHandler
handler.RejRec.level=WARN
handler.RejRec.formatter=RejRec
handler.RejRec.properties=append,autoFlush,enabled,suffix,fileName
handler.RejRec.append=true
handler.RejRec.autoFlush=true
handler.RejRec.enabled=true
handler.RejRec.suffix=.yyyy-MM-dd
handler.RejRec.fileName=E:\Docs\WithoutBook\DID\jboss-eap-6.2\standalone\log\RejectedRecords.log

log4j.xml:
<log4j:configuration>
<appender name="ASYNC" class="org.apache.log4j.AsyncAppender">
        <appender-ref ref="LOG"/>
</appender>

<appender name="MEETING-APP-LOG" class="org.apache.log4j.DailyRollingFileAppender">
<param name="File" value="E:/Softwares/glassfish_dump/glassfish/domains/domain1/logs/meeting_app.log" />
<param name="Append" value="true"/> 
<param name="DatePattern" value="'.'yyyy-MM-dd-a"/>
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d{yyyy-MM-dd} %d{HH:mm:ss,SSS} %-5p [%t] %c - %m%n" />
</layout>
</appender>

  <logger name="com.withoutbook" additivity="false">
         <level value="warn"/>
         <appender-ref ref="MEETING-APP-LOG"/>
</logger>

     <root>
         <priority value="debug"/>
         <appender-ref ref="ASYNC"/>
         <appender-ref ref="ERROR-LOG"/>
</root>
</log4j:configuration>
保存以便复习

保存以便复习

收藏此条目、标记为困难题,或将其加入复习集合。

打开我的学习资料库
这有帮助吗?
添加评论 查看评论
问题 5

What are the system properties checked by log4j?

The system properties checked by log4j are

  • Log4j debug, if true, log4j will show internal debugging messages to the console
  • defaultInitOverride, if true, log4j will not execute default initialization
  • configuration, URL for default initialization configuration file
  • configurationClass, Class name for configurator to execute default initialization configuration file
  • ignoreTCL, if true, the thread class loader will be overlooked when loading classes
保存以便复习

保存以便复习

收藏此条目、标记为困难题,或将其加入复习集合。

打开我的学习资料库
这有帮助吗?
添加评论 查看评论
问题 7

How can you get multiple processes to log into the same file?

You may have each process log to a socket Appender. The receiving socket server can receive all the events and send them to a single log file.

保存以便复习

保存以便复习

收藏此条目、标记为困难题,或将其加入复习集合。

打开我的学习资料库
这有帮助吗?
添加评论 查看评论
问题 8

What is the difference between Threshold and LevelRangeFilter in log4j?

Both Threshold and LevelRangeFilter do the same thing.

However, the threshold should be faster. Filters enable you to implement your own logic, and you can also link them together if required. If you need a basic threshold functionality, then the “threshold” function will be enough.

保存以便复习

保存以便复习

收藏此条目、标记为困难题,或将其加入复习集合。

打开我的学习资料库
这有帮助吗?
添加评论 查看评论
问题 9

What are the format characters used in log4j?

The format characters used in log4j are

  • L – it is used to output the line number from where the logging request was processed or issued
  • m – It is used to output the application-supplied message related to the logging event
  • p – It is used to output the priority of the logging event
  • C – It is used to output the class name of the caller issuing the logging request

When any number is used along with the character it means the priority of the logging event should be justified to a width of 4 characters.

保存以便复习

保存以便复习

收藏此条目、标记为困难题,或将其加入复习集合。

打开我的学习资料库
这有帮助吗?
添加评论 查看评论
问题 10

Mention what is the best way to migrate from java.util logging to apache log4j?

The best way to migrate from java.util logged to log4j is to use the global file search/replace method.  It will replace with “org.apache.log4j.Logger”.

Then verify the project with the build.

保存以便复习

保存以便复习

收藏此条目、标记为困难题,或将其加入复习集合。

打开我的学习资料库
这有帮助吗?
添加评论 查看评论
问题 11

Why do you get multiple copies of the message in log file sometime?

There could be two reasons why this might happen:

  • Repeated configuration of log4j
  • Attaching the same appenders to multiple loggers
保存以便复习

保存以便复习

收藏此条目、标记为困难题,或将其加入复习集合。

打开我的学习资料库
这有帮助吗?
添加评论 查看评论

用户评价最有帮助的内容:

版权所有 © 2026,WithoutBook。