[LOG4J2-3435] Possibly invalid module-info.class in jog4j-api-2-17.1.jar

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Not A Bug
• Affects Version/s: 2.17.1
• Component/s: API

Environment

SAP WEB AS 7.50.20 (AIX)
JVM 1.8 (SAP JVM)

• Assignee: Unassigned
• Reporter: Michael Voss
• Created: 15/Mar/22 10:18
• Updated: 15/Mar/22 10:55
• Resolved: 15/Mar/22 10:55

Description

When deploying an application containing log4j-api-2.17.1.jar retrieved via maven dependency

<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-api</artifactId>
    <version>2.17.1</version>
</dependency>

onto a SAP WebApplicationServer running Java 8.1, the deployment (using NWDI) fails reporting 

com.sap.engine.services.dc.api.deploy.DeployException: [ERROR CODE DPL.DCAPI.1027] DeploymentException.
...
Caused by: com.sap.engine.library.bytecode.cf.CFException: Invalid constant pool tag, 19 at index 5.

This error is thrown due to an alleged java version conflict, although log4j 2.17.1 requires Java 8 only and the application server (and it's deployment mechanism) is running on Java 8. After evaluating the feedback from SAP support, it seems the attached file module-info.class located in log4j-api-2.17.1.jar/META-INF/versions/9/ is the reason for this behaviour. If we remove this file from the jar, the deployment is successful.