[WFCORE-3765] Remove org.jboss.msc from the modular system class path

[jamezp]

https://issues.jboss.org/browse/WFCORE-3765

Follows up on #3229 to declare remove org.jboss.msc from the modular system class path.

[dmlloyd]

So the change is just to make it not be provided?

[jamezp]

@dmlloyd Correct. It's required on the class path for the ManagedProcessFactory.createXxx() to work.

[bstansberry]

@jamezp Can you link where this is used on the embedding app side? I'm not seeing it.

edit: I do see this, where org.jboss.msc is being included as a system package on the JBM side:

src/main/java/org/wildfly/core/embedded/EmbeddedProcessFactory.java:            StringBuilder packages = new StringBuilder("org.jboss.modules,org.jboss.msc,org.jboss.dmr,org.jboss.threads,org.jboss.as.controller.client");

So that would probably necessitate this change. I don't see why that package needs to be in the list though; nothing from it is used internally on the embedding app side, and nor is anything from it exposed to caller. It might be cruft. I don't know if removing that would somehow be a breaking change though. I can't think how it would be.

[jamezp]

@bstansberry Yes that's where it's at. It's trying to load MSC from the modular system class loader.

Exception in thread "main" java.lang.IllegalStateException: WFLYEMB0019: Cannot create standalone server using factory: public static org.wildfly.core.embedded.StandaloneServer org.wildfly.core.embedded.EmbeddedStandaloneServerFactory.create(java.io.File,org.jboss.modules.ModuleLoader,java.util.Properties,java.util.Map,java.lang.String[])
	at org.wildfly.core.embedded.EmbeddedProcessFactory.createManagedProcess(EmbeddedProcessFactory.java:301)
	at org.wildfly.core.embedded.EmbeddedProcessFactory.createStandaloneServer(EmbeddedProcessFactory.java:183)
	at org.wildfly.reproducer.Main.main(Main.java:57)
Caused by: java.lang.NoClassDefFoundError: org/jboss/msc/value/Value
	at org.wildfly.core.embedded.EmbeddedStandaloneServerFactory.create(EmbeddedStandaloneServerFactory.java:101)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.wildfly.core.embedded.EmbeddedProcessFactory.createManagedProcess(EmbeddedProcessFactory.java:296)
	... 2 more
Caused by: java.lang.ClassNotFoundException: org.jboss.msc.value.Value
	at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	at org.jboss.modules.JDKSpecific.getSystemClass(JDKSpecific.java:180)
	at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:395)
	at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:116)
	... 8 more

[bstansberry]

@jamezp It's cruft left over from the pre-WildFly Core embedded, where StandaloneServer exposed MSC:

https://github.com/jbossas/jboss-eap/blob/6.x/embedded/src/main/java/org/jboss/as/embedded/StandaloneServer.java#L64

That got removed along the way.

Unless @dmlloyd can think of a way that the MSC lib used by the appserver also being visible to the embedding app would be useable (e.g. some static methods in MSC that would let the embedding app hack into the appserver ServiceContainer), I think we should just remove org.jboss.msc from the system package list. And even if there is a way to hack like that we probably should cut it off.

[jamezp]

@bstansberry I think that makes sense. I'll place a hold label on this until we make a decision the.

[dmlloyd]

I'm OK with removing it.

[jamezp]

The dependency change has been removed and org.jboss.msc package has been removed from the modular system packages.

[wildfly-ci]

Core - Full Integration Build 7287 outcome was FAILURE using a merge of 7816507
Summary: Execution timeout (new); tests passed: 4174, ignored: 136 Build time: 02:30:48