[Bug] Wrong Spring plugin activated: Spring 6.x plugin incorrectly triggers for Spring 5.3.13 due to imprecise witness class

[zJiaJun]

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• I had searched in the issues and found no similar issues.

Apache SkyWalking Component

Java Agent (apache/skywalking-java)

What happened

The Spring 6.x plugin (mvc-annotation-6.x-plugin) is being incorrectly activated when using Spring Framework 5.3.13, causing runtime errors due to API incompatibilities between Spring 5.x and Spring 6.x.

The issue is in the witness class selection in AbstractSpring6Instrumentation:

// AbstractSpring6Instrumentation.java
public static final String WITNESS_CLASSES = "org.springframework.web.servlet.resource.HttpResource";

The HttpResource class exists in Spring Framework since version 5.0 (as documented here), making it an imprecise witness class for detecting Spring 6.x.

Error Details

ERROR 2025-06-26 12:06:24.943 XNIO-1 task-4 InstMethodsInter : class[class org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod] after method[getBean] intercept failure java.lang.NoSuchMethodError: org.springframework.web.context.request.ServletRequestAttributes.getRequest()Ljakarta/servlet/http/HttpServletRequest; at org.apache.skywalking.apm.plugin.spring.mvc.v6.GetBeanInterceptor.afterMethod(GetBeanInterceptor.java:51)

Analysis

1. Spring 5.3.13 uses javax.servlet.* APIs
2. Spring 6.x migrated to jakarta.servlet.* APIs
3. The ServletRequestAttributes.getRequest() method returns different types:
   • Spring 5.x: javax.servlet.http.HttpServletRequest
   • Spring 6.x: jakarta.servlet.http.HttpServletRequest
4. Since HttpResource exists in both Spring 5.x and 6.x, the witness class check passes incorrectly

What you expected to happen

• Spring 5.x applications should activate the mvc-annotation-5.x-plugin
• Spring 6.x applications should activate the mvc-annotation-6.x-plugin

How to reproduce

• SkyWalking Version: 9.1.0
• Spring Framework Version: 5.3.13
• Java Version: 1.8

Anything else

Replace the witness class in AbstractSpring6Instrumentation with a class that only exists in Spring 6.x
Any recommended classes?

If my thinking is wrong, please tell me.

Are you willing to submit a pull request to fix on your own?

• Yes I am willing to submit a pull request on my own!

Code of Conduct

• I agree to follow this project's Code of Conduct

[wu-sheng]

javax VS Jakata is a long story. AFAIK, Spring supports both of them.

Spring6 plugins worked in the test scenarios. https://github.com/apache/skywalking-java/blob/main/test/plugin/scenarios/spring-6.x-scenario/support-version.list

If you need Jakata, we may need to split that interceptor into two for javax and Jakata, rather than just replacement. It will break another group of people.