'Log4j 2: How to enable ANSI colours on Windows console?
I try to use Windows 10 command line to print colored messages on console, but with no success. According to the Log4j 2 documentation, I should add the Jansi jar to my print application and set property log4j.skipJansi
to false
for enabling ANSI support on Windows. Could you, please, check and say what I did wrong:
- Following code is my current work:
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
public class LoggerTest {
private static final Logger logger = LogManager.getLogger();
public static void main(String[] args) throws Exception {
logger.info("Hello!");
}
}
- Following code is Log4j 2 configuration file:
<?xml version="1.0" encoding="UTF-8"?>
<Configuration>
<Properties>
<Property name="log4j.skipJansi" value="false"/>
</Properties>
<Appenders>
<Console name="ConsoleAppender" target="SYSTEM_OUT">
<PatternLayout>
<disableAnsi>false</disableAnsi>
<Pattern>%style{%d [%t] %c %p: %m}{yellow}%n%ex</Pattern>
</PatternLayout>
</Console>
</Appenders>
<Loggers>
<Root level="INFO">
<AppenderRef ref="ConsoleAppender"/>
</Root>
</Loggers>
</Configuration>
- The contents of \lib directory:
log4j-core-2.12.1.jar
log4j-api-2.12.1.jar
jansi-1.18.jar
- And the Windows compileAndRun.bat file:
@echo off
javac -cp lib\*;. LoggerTest.java
java -cp lib\*;. LoggerTest
pause
exit
However, the output in the command line is still not coloured. This is what I see:
So, the message contains ANSI escape codes, but they are not interpreted by command line. Though, if I try to copy/paste this output and echo it directly using another bat-file, then I see the coloured message.
Solution 1:[1]
It worked for when I add disableAnsi="false"
propriety to <PatternLayout>
<Appenders>
<Console name="ConsoleAppender" target="SYSTEM_OUT">
<PatternLayout
pattern="%highlight{%p} %logger{-2} - %m{FATAL=red blink,ERROR=red, WARN=yellow bold, INFO=green, DEBUG=green bold}%n" disableAnsi="false"/>
</Console>
</Appenders>
Solution 2:[2]
This is answer how to enable colors with latest log4j on windows 7:
openjdk 14
log4j 2.14.1
jansi 1.18
Configuration:
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="INFO">
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %highlight{%-5level}{FATAL=red blink, ERROR=red bold, WARN=yellow bold, INFO=magenta, DEBUG=green, TRACE=blue} %logger{36} - %msg%n"/>
</Console>
</Appenders>
<Loggers>
<Root level="debug">
<AppenderRef ref="Console"/>
</Root>
</Loggers>
</Configuration>
The key point is to pass -DLOG4J_SKIP_JANSI=false
to JVM. Solution was found in this user guide.
Solution 3:[3]
Try executing this command: "reg add HKCU\Console /v VirtualTerminalLevel /t REG_DWORD /d 1"
In Java:
Runtime.getRuntime().exec("reg add HKCU\\Console /v VirtualTerminalLevel /t REG_DWORD /d 1");
Solution 4:[4]
I had to include both Jansi and Jcabi for cross-OS rendering -
<dependency>
<groupId>org.fusesource.jansi</groupId>
<artifactId>jansi</artifactId>
<version>1.18</version>
<optional>true</optional>
</dependency>
<dependency>
<groupId>com.jcabi</groupId>
<artifactId>jcabi-log</artifactId>
<version>LATEST</version>
<optional>true</optional>
</dependency>
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
Solution | Source |
---|---|
Solution 1 | Ak.tech |
Solution 2 | Pavel_K |
Solution 3 | IOExeeption |
Solution 4 | Marc Magon |