Thank you so much Piotr for detailed explanation of bug. I will create JIRA 
ticket ASAP and shortly will reply with details also you have asked.

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From: Piotr P. Karwasz <>
Sent: Saturday, March 5, 2022 7:23:34 PM
To: Log4J Users List <>
Subject: Re: java.lang.ClassCastException: 
org.apache.log4j.bridge.AppenderWrapper cannot be cast to 

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Hi Pooja,

On Sat, Mar 5, 2022 at 1:48 PM Pooja Pandey
<> wrote:
> Hi Piotr,
> I don’t understand what is the bug?? Can you please help me with JIRA
> ticket summary and description.

The bug is that if you use a native Log4j 1.2 appender (a derivative
class of org.apache.log4j.FileAppender for example) a call to
`Logger.getAppender(String)` gives you an AppenderWrapper of an
AppenderAdapter instead of the original class. Such useless
encapsulations should not be present, but apparently we missed some.
Summarizing "Log4j 1.x bridge Logger.getAppender returns a wrapped
In the Jira ticket just describe your exact situation: are you using a
configuration file or are you adding the appenders in code? Are you
always using a LoggerFactory?
My wild guess is that you configure a subclass of
org.apache.log4j.FileAppender (let's call it com.example.FileAppender)
in a configuration file. In your code you call `Logger.getAppender()`
and you get an AppenderWrapper instead of com.example.FileAppender. If
the guess is true, it is an easy fix.


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