ppkarwasz commented on PR #1652: URL: https://github.com/apache/logging-log4j2/pull/1652#issuecomment-1660870439
Hi @SebHeuze, The story is a little bit more complicated than that. Before Spring Boot 2.4.0 the only way to select a Spring Boot [`LoggingSystem`](https://docs.spring.io/spring-boot/docs/current/api/org/springframework/boot/logging/LoggingSystem.html) was to set a system property: ``` org.springframework.boot.logging.LoggingSystem=org.apache.logging.log4j.spring.boot.Log4j2SpringBootLoggingSystem ``` This method is **still valid** with all the Spring Boot versions mentioned in the docs. Log4j2 2.17.2 or earlier used a `log4j2.system.properties` file (cf. [System Properties](https://logging.apache.org/log4j/2.x/manual/configuration.html#SystemProperties)) embedded in the `log4j-spring-boot` JAR file to set this property. This method **effectively** prevents the usage of any other `LoggingSystem` (including the original Spring Boot's `Log4j2LoggingSystem`) and was removed in #777. Since Spring Boot 2.4.0 a new mechanism to register a `LoggingSystem` is available: `spring.factories` (cf. [`SpringFactoriesLoader`](https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/core/io/support/SpringFactoriesLoader.html). This is the mechanism adopted by Log4j 2.18.0 and later versions. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: notifications-unsubscr...@logging.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
