Build failed in Jenkins: java-openws-nightly #110

[Shibboleth Jenkins]

See <https://build.shibboleth.net/jenkins/job/java-openws-nightly/110/>

------------------------------------------
Started by upstream project "java-xmltooling-nightly" build number 110
originally caused by:
 Started by upstream project "java-parent-project-v2-nightly" build number 108
 originally caused by:
  Started by upstream project "trigger-nightly-v2" build number 281
  originally caused by:
   Started by timer
Building on master in workspace <https://build.shibboleth.net/jenkins/job/java-openws-nightly/ws/>
Updating https://svn.shibboleth.net/java-openws/branches/REL_1 at revision '2016-01-28T03:48:36.873 -0500'
At revision 485

No changes for https://svn.shibboleth.net/java-openws/branches/REL_1 since the previous build
[workspace] $ /opt/maven/bin/mvn -Dmaven.repo.local=<https://build.shibboleth.net/jenkins/job/java-openws-nightly/ws/.repository> clean -Prelease,central-disabled -U deploy site
Exception in thread "main" java.lang.UnsupportedClassVersionError: org/apache/maven/cli/MavenCli : Unsupported major.minor version 51.0
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
	at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
	at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClassFromSelf(ClassRealm.java:401)
	at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:42)
	at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271)
	at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:254)
	at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239)
	at org.codehaus.plexus.classworlds.launcher.Launcher.getMainClass(Launcher.java:144)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:266)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
	at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
	at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Build step 'Invoke top-level Maven targets' marked build as failure
[CHECKSTYLE] Skipping publisher since build result is FAILURE
[htmlpublisher] Archiving HTML reports...
[htmlpublisher] Archiving at PROJECT level <https://build.shibboleth.net/jenkins/job/java-openws-nightly/ws/target/site> to /var/lib/jenkins/jobs/java-openws-nightly/htmlreports/Site_Report
Publishing Javadoc
TestNG Reports Processing: START
Looking for TestNG results report in workspace using pattern: **/target/surefire-reports/testng-results.xml
testng-results.xml was last modified before this build started. Ignoring it.
Saving reports...
Found matching files but did not find any TestNG results.