How Can I Add Console Appender In Logger Object Using log4j-over-slf4j Dependency? - log4j

I can't be able to add console appender using logger.addAppender method with log4j-over-slf4j 1.7.x dependency. Moreover, I am unable to set target of that particular Console Appender(i.e., SYSTEM_OUT/SYSTEM_ERR).
I have initialized a console appender object and tried to push that reference into addAppender method by typecasting that reference to Appender. But in that case I am unable to set Target/WriterLocation(i.e., SYSTEM_OUT/SYSTEM_ERR) for console appender reference. I have used the below code snippet-
ConsoleAppender ca = new ConsoleAppender();
ca.setWriter(new OutputStreamWriter(System.out)); // this line is not compatible with log4j-over-slf4j jar
ca.setLayout(new PatternLayout("%-5p [%t]: %m%n"));
logger.addAppender(ca);
Please help me to sort out this problem.

What you are doing doesn't make a lot of sense. log4j-over-slf4j will route calls like logger.debug(), logger.info(), etc to slf4j and then presumably to some other logging framework to be logged. Your code is trying to manipulate log4j 1 objects which won't be involved in logging since you are routing log events to SLF4J (which is why many of them aren't supported by log4j-over-slf4j).
In order to help you we would know what logging implementation you really want to use.

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The method getRootLogger() is undefined for the type Logger migration from Log4j 1.x to 2.x

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#Mock
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I use logger org.apache.commons.logging.Log.
File log4j.properties is:
log4j.rootCategory=INFO, S
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
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log4j.logger.org.w3c.tidy=INFO
...................
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I created a custom appender that I could pass the TestContext to, and use the WriteLine method on that for logging.
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https://gist.github.com/dropthemic/f360c389c35758bbb94e67b3aee09157
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We have a modular application where modules have their own log4j logs (i.e. communication log and error log). The appenders and categories for these are all configured in the core log4j XML, but not all modules are always installed.
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Example:
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<Policies>
<SizeBasedTriggeringPolicy size="1MB"/>
</Policies>
<DefaultRolloverStrategy max="5"/>
</RollingFile>
More details here: https://logging.apache.org/log4j/2.x/manual/appenders.html#RollingRandomAccessFileAppender
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public void startLog() {
SimpleDateFormat sdf_long = new SimpleDateFormat("yyyy_MM_dd_HH_mm_ss");
FileAppender fa = new FileAppender();
fa.setName("foo");
fa.setFile(sdf_long.format(new Date()) + ".log");
fa.setLayout(new PatternLayout("%d{HH:mm:ss.SSS} %m%n"));
fa.setThreshold(Level.DEBUG);
fa.setAppend(true);
fa.activateOptions();
Logger.getRootLogger().addAppender(fa);
}
public void stopLog() {
Logger.getRootLogger().getAppender("foo").close();
Logger.getRootLogger().removeAppender("foo");
}
My log4j.properties file only configures the console appender. When I want to start logging I call the startLog() method. When I want to log in an other file I call stopLog() first and then startLog() method.

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