Log4j2 RegexFilter pattern does not match

Question

I've got the following lines in my log that I want to exclude, so I wanted to use a RegexFilter to do so:

[INFO ] 2018-05-20 14:52:15.993 [qtp22844606-20] TimingFilter - Request time: 16 ms

[INFO ] 2018-05-20 14:52:18.998 [qtp22844606-17] TimingFilter - Request time: 15 ms

[INFO ] 2018-05-20 14:52:22.001 [qtp22844606-20] TimingFilter - Request time: 0 ms

[INFO ] 2018-05-20 14:52:24.992 [qtp22844606-17] TimingFilter - Request time: 0 ms

My config looks as such:

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
    <Appenders> 
        <Console name="console" target="SYSTEM_OUT">
            <RegexFilter regex=".*TimingFilter.*" useRawMsg="true" onMatch="DENY" onMismatch="ACCEPT"/>
            <PatternLayout   pattern="[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n" />
        </Console>
    </Appenders>
    <Loggers>
        <Root level="info" additivity="false">
            <appender-ref ref="console" />
        </Root>
    </Loggers>
</Configuration>

When switching "ACCEPT" and "DENY" no message gets through, so the RegexFilter per se seems to get picked up. I also tried "\\bTimingFilter\\b", ".*\\bTimingFilter\\b.*" without success.

I'm using Log4J 2.11.

Can you give any hints what I do wrong? I checked all other RegexFilter related questions here and also other sites (that's where I got the suggestions for the Regex Patterns I tried), but nothing seems to work. I also checked the patterns on https://regex101.com/ against my log and there they matched correctly.

Answer 1

This happens because you have useRawMsg="true" switch it to useRawMsg="false". See the log4j2 manual :

If true the unformatted message will be used, otherwise the formatted message will be used. The default value is false.

EDIT:

I didn't look closely enough at your configuration and your output, so I apologize for that. The reason the RegexFilter does not work for you is that you're using it to try to filter based on the name of the logger . As per the log4j2 manual :

The RegexFilter allows the formatted or unformatted message to be compared against a regular expression.

To prevent a logger from logging any messages you have several options. I will illustrate one of them with some sample code below.

Here is a main class that runs a TimingFilter class:

package example;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class Main {

private static final Logger log = LogManager.getLogger();

    public static void main(String[] args){
        log.info("Here's some info!");
        log.error("Some erorr happened!");
        TimingFilter.main(null);
    }

}

Here is the TimingFilter class:

package example;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class TimingFilter {

    private static final Logger log = LogManager.getLogger();

    public static void main(String[] args){
        log.info("Here's some info!");
        log.error("Some erorr happened!");
    }
}

Here is a sample log4j2.xml file:

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
    <Appenders> 
        <Console name="console" target="SYSTEM_OUT">
            <PatternLayout   pattern="[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n" />
        </Console>
    </Appenders>
    <Loggers>
        <Logger level="off" name="example.TimingFilter">
        </Logger>
        <Root level="info" additivity="false">
            <appender-ref ref="console" />
        </Root>
    </Loggers>
</Configuration>

Notice how I have configured the example.TimingFilter logger so that its level is "off". This prevents any logging from this logger.

When I run the Main class the output only contains messages from Main :

[INFO ] 2018-05-22 23:23:30.473 [main] Main - Here's some info!
[ERROR] 2018-05-22 23:23:30.474 [main] Main - Some erorr happened!