Suspicious NoClassDefFoundError/ClassNotFoundException in trivial BindingGeneratorUtilTest when running Maven in parallel

I've hit the NoClassDefFoundError/ClassNotFoundException below when running parallel Maven build, in mdsal (root):

mvn -T 1.5C clean install

Q: Is Maven (maven-surefire-plugin) known to be simply completely broken for parallel Maven builds, or should this work, normally?

Could this be an indication of a bigger problem somewhere in ODL code? As you know, I don't know much about anything just yet (but am eager to learn..), but have stumbled upon our org.opendaylight.yangtools.util.ClassLoaderUtils (AKA @Deprecated org.opendaylight.yangtools.yang.binding.util.ClassLoaderUtils - can I put in a Gerrit change to cleanly remove that?) related to ClassLoader and Thread setContextClassLoader magic .. perhaps something subtle wrong in that area?

FYI I'm also trying to get to the bottom of YANGIDE-10 (class loading problem in yangide) - wondering if there could be a connection.

[INFO] — maven-surefire-plugin:2.18.1:test (default-test) @ mdsal-binding-generator-util —
[INFO] Surefire report directory: /home/vorburger/dev/ODL/git/mdsal/binding/mdsal-binding-generator-util/target/surefire-reports
Downloading: http://nexus.opendaylight.org/content/repositories/public/org/apache/maven/surefire/surefire-junit3/2.18.1/surefire-junit3-2.18.1.pom
Downloaded: http://nexus.opendaylight.org/content/repositories/public/org/apache/maven/surefire/surefire-junit3/2.18.1/surefire-junit3-2.18.1.pom (2 KB at 3.0 KB/sec)
Downloading: http://nexus.opendaylight.org/content/repositories/public/org/apache/maven/surefire/surefire-junit3/2.18.1/surefire-junit3-2.18.1.jar
Downloading: http://nexus.opendaylight.org/content/repositories/opendaylight.snapshot/org/opendaylight/yangtools/mockito-configuration/1.0.0-SNAPSHOT/mockito-configuration-1.0.0-20160511.100431-121.jar
Downloaded: http://nexus.opendaylight.org/content/repositories/public/org/apache/maven/surefire/surefire-junit3/2.18.1/surefire-junit3-2.18.1.jar (25 KB at 37.3 KB/sec)

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T E S T S
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Downloaded: http://nexus.opendaylight.org/content/repositories/opendaylight.snapshot/org/opendaylight/yangtools/mockito-configuration/1.0.0-SNAPSHOT/mockito-configuration-1.0.0-20160511.100431-121.jar (11 KB at 19.8 KB/sec)
Running org.opendaylight.yangtools.binding.generator.util.BindingTypesTest
Tests run: 2, Failures: 2, Errors: 0, Skipped: 0, Time elapsed: 0.92 sec <<< FAILURE! - in org.opendaylight.yangtools.binding.generator.util.BindingTypesTest
org.opendaylight.yangtools.binding.generator.util.BindingTypesTest.testAugmentable() Time elapsed: 0.893 sec <<< FAILURE!
java.lang.NoClassDefFoundError: org/junit/Assert
at org.opendaylight.yangtools.binding.generator.util.BindingTypesTest.testAugmentable(BindingTypesTest.java:48)
Caused by: java.lang.ClassNotFoundException: org.junit.Assert
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 13 more

org.opendaylight.yangtools.binding.generator.util.BindingTypesTest.testChildOf() Time elapsed: 0.001 sec <<< FAILURE!
java.lang.NoClassDefFoundError: org/junit/Assert
at org.opendaylight.yangtools.binding.generator.util.BindingTypesTest.testChildOf(BindingTypesTest.java:54)

Results :

Failed tests:
org.opendaylight.yangtools.binding.generator.util.BindingTypesTest#testAugmentable NoClassDefFoundError
org.opendaylight.yangtools.binding.generator.util.BindingTypesTest#testChildOf NoClassDefFoundError

Tests run: 2, Failures: 2, Errors: 0, Skipped: 0

[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO]
[INFO] mdsal-parent ....................................... SUCCESS [ 16.750 s]
[INFO] mdsal-artifacts .................................... SUCCESS [ 11.413 s]
[INFO] mdsal-common-api ................................... SUCCESS [01:51 min]
[INFO] mdsal-dom .......................................... SUCCESS [ 4.306 s]
[INFO] mdsal-dom-api ...................................... SKIPPED
[INFO] mdsal-dom-spi ...................................... SKIPPED
[INFO] mdsal-dom-inmemory-datastore ....................... SKIPPED
[INFO] mdsal-dom-broker ................................... SKIPPED
[INFO] mdsal-binding ...................................... SUCCESS [ 5.822 s]
[INFO] yang-binding ....................................... SUCCESS [01:47 min]
[INFO] mdsal-binding-generator-api ........................ SUCCESS [ 39.720 s]
[INFO] mdsal-binding-generator-util ....................... FAILURE [ 8.858 s]
[INFO] mdsal-binding-generator-impl ....................... SKIPPED
[INFO] binding-parent ..................................... SUCCESS [ 16.663 s]
[INFO] model-parent ....................................... SUCCESS [ 2.863 s]
[INFO] mdsal-binding-java-api-generator ................... SKIPPED
[INFO] maven-sal-api-gen-plugin ........................... SKIPPED
[INFO] yang-ext ........................................... SKIPPED
[INFO] mdsal-binding-test-model ........................... SKIPPED
[INFO] mdsal-binding-dom-codec ............................ SKIPPED
[INFO] general-entity ..................................... SKIPPED
[INFO] mdsal-binding-api .................................. SKIPPED
[INFO] mdsal-binding-util ................................. SKIPPED
[INFO] mdsal-binding-dom-adapter .......................... SKIPPED
[INFO] features-mdsal ..................................... SKIPPED
[INFO] md-sal ............................................. SUCCESS [ 4.043 s]
[INFO] mdsal-binding2 ..................................... SUCCESS [ 3.362 s]
[INFO] mdsal-binding2-spec ................................ SUCCESS [01:45 min]
[INFO] model-iana ......................................... SKIPPED
[INFO] iana-afn-safi ...................................... SKIPPED
[INFO] model-ietf ......................................... SKIPPED
[INFO] ietf-type-util ..................................... SKIPPED
[INFO] ietf-inet-types .................................... SKIPPED
[INFO] ietf-yang-types-20130715 ........................... SKIPPED
[INFO] ietf-interfaces .................................... SKIPPED
[INFO] iana-if-type-2014-05-08 ............................ SKIPPED
[INFO] ietf-restconf ...................................... SKIPPED
[INFO] ietf-yang-types .................................... SKIPPED
[INFO] opendaylight-l2-types .............................. SKIPPED
[INFO] ietf-ted ........................................... SKIPPED
[INFO] ietf-topology ...................................... SKIPPED
[INFO] ietf-topology-l3-unicast-igp ....................... SKIPPED
[INFO] ietf-topology-isis ................................. SKIPPED
[INFO] ietf-topology-ospf ................................. SKIPPED
[INFO] ietf-network-2015-06-08 ............................ SKIPPED
[INFO] ietf-inet-types-2013-07-15 ......................... SKIPPED
[INFO] features-mdsal-model ............................... SKIPPED
[INFO] mdsal-model-artifacts .............................. SUCCESS [ 11.409 s]
[INFO] iana-if-type ....................................... SKIPPED
[INFO] md-sal ............................................. SKIPPED
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 03:04 min (Wall Clock)
[INFO] Finished at: 2016-05-11T12:07:18+02:00
[INFO] Final Memory: 181M/945M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-surefire-plugin:2.18.1:test (default-test) on project mdsal-binding-generator-util: Execution default-test of goal org.apache.maven.plugins:maven-surefire-plugin:2.18.1:test failed: There was an error in the forked process
[ERROR] java.lang.NoClassDefFoundError: org/junit/rules/ExpectedException
[ERROR] at org.opendaylight.yangtools.binding.generator.util.BindingGeneratorUtilTest.<init>(BindingGeneratorUtilTest.java:60)
[ERROR] at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
[ERROR] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
[ERROR] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
[ERROR] at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
[ERROR] at java.lang.Class.newInstance(Class.java:442)
[ERROR] at org.apache.maven.surefire.junit.PojoTestSet.<init>(PojoTestSet.java:67)
[ERROR] at org.apache.maven.surefire.junit.JUnit3Provider.createTestSet(JUnit3Provider.java:116)
[ERROR] at org.apache.maven.surefire.junit.JUnit3Provider.invoke(JUnit3Provider.java:106)
[ERROR] at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:203)
[ERROR] at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:155)
[ERROR] at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:103)
[ERROR] Caused by: java.lang.ClassNotFoundException: org.junit.rules.ExpectedException
[ERROR] at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
[ERROR] at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
[ERROR] at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
[ERROR] at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
[ERROR] ... 12 more
[ERROR] -> [Help 1]