[LOG4J2-2006] RollingFile createOnDemand validation

[ramanathan1504]

PR Notes: RollingFile createOnDemand validation

Scope

• Module tested: spring-boot-test only
• core-java-test and log4j2-web-test left unchanged

What was run

• Local dependency check confirmed 2.26.0-SNAPSHOT artifacts resolved from ~/.m2
• Startup timing probes from SpringBootTestApp#printLogPathState used as source of truth

Results (2.26.0-SNAPSHOT)

createOnDemand="true" (default log4j2.xml)

• main-entry: dir=false app.log=false app-json.log=false
• after LogManager.getLogger: dir=false app.log=false app-json.log=false
• after first log event: dir=true app.log=true app-json.log=true

Conclusion: directory and files are created on first log event (expected on-demand behavior).

createOnDemand="false" (log4j2-createOnDemand-false.xml)

• main-entry: dir=false app.log=false app-json.log=false
• after LogManager.getLogger: dir=true app.log=true app-json.log=true
• after first log event: dir=true app.log=true app-json.log=true

Conclusion: eager creation occurs before first log event (expected non-demand behavior).