Adding Spring Boot Actuator Metrics to a Jersey App

Spring Boot Actuator adds a number of health monitoring endpoints to support monitoring of your Spring Boot based applications. To add to an existing Spring Boot app, you just add a dependency on spring-boot-starter-actuator as described here.

This works out of the box for a Spring MVC based Spring Boot app, but if you’re building JAX-RS endpoints using Jersey, by default the Jersey resources and Actuator resources both get mapped to the root ( / ), so you need to map either Jersey or Actuator to something other than /. You can easily re-map Actuator be adding this line to application.properties (change /system as needed):

server.servlet-path=/system

This is described here: http://docs.spring.io/spring-boot/docs/current/reference/html/howto-actuator.html#howto-use-actuator-with-jersey

Hibernate OGM / JAX-RS / JAX-WS redeployment issue on WildFly8.2: java.lang.NoSuchMethodException: org.objectweb.asm.MethodWriter.visitLabel

I’ve been struggling with failing redeploys on WildFly8.2 while I’m developing my app. If the app is deployed, on first server start it starts up fine, but then if I redeploy some code changes I get this NoSuchMethodException in the asm library, suggesting I’ve got some conflict of versions of the asm library used by my app:

Caused by: java.lang.NoSuchMethodException: org.objectweb.asm.MethodWriter.visitLabel(org.objectweb.asm.Label)
 at java.lang.Class.getMethod(Class.java:1773) [rt.jar:1.8.0_20]
 at org.apache.cxf.common.util.ReflectionInvokationHandler.invoke(ReflectionInvokationHandler.java:85)
 ... 28 more

Luckily I came across this post with the same error, putting me on the right direction about the possibility of my app being packaged with a conflicting version of asm. Looking at a ‘mvn dependency:tree’ on my app, I could see asm being pulled in from my use of Hibernate OGM and Jersey as transitive dependencies.

Despite trying to add excludes to not get asm included in the packaging of my app, I eventually gave up and decided to just remove my luckily minimal use of Hibernate OGM. I think the issue was caused my OGM’s deployment of modules onto the WildFly server, one of which was asm. After I had removed OGM from my app, removed the modules, I was back to speedy redeploys of my app.

I’m sure there’s a way to get OGM to deploy happily, or maybe I had just ran across an asm version conflict with other libraries my app is using (Jersey?), but I don’t have time right now to deal with it. Another project for another day ­čÖé