The color is missing from my log messages. Why?

[NadChel]

Why doesn't this log4j configuration work? I mean the log messages themselves are correct, but the color is missing. The messages are all white, even, for example, WARN messages that are supposed to be in yellow

Configuration:

  Appenders:
    Console:
      name: CONSOLE
      PatternLayout:
        pattern: "%highlight{%d{DATE}%n%-5p [%t] : %m%n}"
      target: SYSTEM_OUT
    File:
      name: FILE
      PatternLayout:
        pattern: "%highlight{%d{DATE}%n%-5p [%t] : %m%n}"
      fileName: "src/main/resources/log.txt"
      append: false
  Loggers:
    Root:
      level: info
      AppenderRef:
         - ref: FILE
         - ref: CONSOLE

My logging dependency is this (I put an @Slf4j annotation from the Lombok library):

        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-slf4j2-impl</artifactId>
            <version>2.20.0</version>
        </dependency>

Example message (it's in white):

26 авг. 2023 02:43:30,917
WARN  [AWT-EventQueue-0] : Bass Drum is not found in the current instrument map – the sound may not fully match the pattern

[ppkarwasz]

You are probably using Windows. Since by default cmd.exe does not support ANSI escapes, they are disabled on Windows and enabled on all other platforms.

To enable Log4j's support for ANSI escapes on Windows you need to:

• either set disableAnsi to false in your layout:

  PatternLayout:
     disableAnsi: false
     pattern: "%highlight{%d{DATE}%n%-5p [%t] : %m%n}"

• or set the system property log4j2.skipJansi to false.

Remark: If you are using cmd.exe, ANSI escape sequences will not be converted into colors unless:

• you set VirtualTerminalLevel to 1 (see this SO question)
• or you add Jansi 1.x to your classpath.

[NadChel]

Thanks a lot, it helped!