[2.1.1-java, maven-play2] NoClassDefFoundError in Tomcat after deploying .war

[kreich]

I've integrated the maven-play2 plugin with my application and everything seems to be working fine until I attempt deployment.  I am getting the following error in my Tomcat logs after starting up Tomcat with the application deployed:

Jul 29, 2013 1:49:42 PM org.apache.catalina.core.ContainerBase addChildInternal

SEVERE: ContainerBase.addChild: start: 

org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[]]

        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)

        at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)

        at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)

        at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)

        at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:977)

        at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1655)

        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)

        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)

        at java.util.concurrent.FutureTask.run(FutureTask.java:166)

        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)

        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)

        at java.lang.Thread.run(Thread.java:722)

Caused by: java.lang.NoClassDefFoundError: scala/Right

        at java.lang.Class.getDeclaredFields0(Native Method)

        at java.lang.Class.privateGetDeclaredFields(Class.java:2308)

        at java.lang.Class.getDeclaredFields(Class.java:1760)

        at org.apache.catalina.util.Introspection.getDeclaredFields(Introspection.java:87)

        at org.apache.catalina.startup.WebAnnotationSet.loadFieldsAnnotation(WebAnnotationSet.java:261)

        at org.apache.catalina.startup.WebAnnotationSet.loadApplicationListenerAnnotations(WebAnnotationSet.java:90)

        at org.apache.catalina.startup.WebAnnotationSet.loadApplicationAnnotations(WebAnnotationSet.java:65)

        at org.apache.catalina.startup.ContextConfig.applicationAnnotationsConfig(ContextConfig.java:405)

        at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:881)

        at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:369)

        at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)

        at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)

        at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5173)

        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)

        ... 11 more

Caused by: java.lang.ClassNotFoundException: scala.Right

        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714)

        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)

        ... 25 more

Up unto this point I've been using the play2-war plugin without issue.  So I disabled the automatic .war production within the plugin configuration (pom.xml), re-compiled and then used the play2-war plugin to generate the .war and that works flawlessly.  I've been up and down the information for the maven plugin and haven't seen mention of this issue. Has anyone else run into this and if so, what was the resolution?

[kreich]

I believe I have found the answer to this issue.  The missing class is scala.Right which doesn't exist in Scala v2.10.  The fact that it's being referenced means that there is a transitive dependency during compilation to an older version of the scala-library.jar (v2.9.1 to be exact).  After looking over the maven-play2-plugin source, the pom.xml is still referencing the older version of the play2-war plugin (v0.8.1) which doesn't work with Play v2.1.0+.  It appears that someone fixed it (although it would have broken WAR builds for older users of Play 2.0), but the merge was unsuccessful.  I've left a few comments on the Github page to see if this can be resolved (https://github.com/nanoko-project/maven-play2-plugin).

Kyle