Oct 19, 2015 9:25:42 AM jenkins.InitReactorRunner$1 onTaskFailed
SEVERE: Failed Loading plugin ruby-runtime
java.io.IOException: Failed to initialize
        at hudson.ClassicPluginStrategy.load(ClassicPluginStrategy.java:441)
        at hudson.PluginManager$2$1$1.run(PluginManager.java:384)
        at org.jvnet.hudson.reactor.TaskGraphBuilder$TaskImpl.run(TaskGraphBuilder.java:169)
        at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:282)
        at jenkins.model.Jenkins$8.runTask(Jenkins.java:915)
        at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:210)
        at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:117)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassCircularityError: org/jruby/RubyClass
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:274)
        at org.jenkinsci.bytecode.ClassWriter.loadClass(ClassWriter.java:97)
        at org.jenkinsci.bytecode.ClassWriter.getCommonSuperClass(ClassWriter.java:64)
        at org.kohsuke.asm5.ClassWriter.getMergedType(ClassWriter.java:1654)
        at org.kohsuke.asm5.Frame.merge(Frame.java:1426)
        at org.kohsuke.asm5.Frame.merge(Frame.java:1374)
        at org.kohsuke.asm5.MethodWriter.visitMaxs(MethodWriter.java:1475)
        at org.kohsuke.asm5.tree.MethodNode.accept(MethodNode.java:833)
        at org.kohsuke.asm5.commons.JSRInlinerAdapter.visitEnd(JSRInlinerAdapter.java:187)
        at org.jenkinsci.bytecode.Transformer$1$1.visitEnd(Transformer.java:107)
        at org.kohsuke.asm5.MethodVisitor.visitEnd(MethodVisitor.java:877)
        at org.kohsuke.asm5.ClassReader.readMethod(ClassReader.java:1021)
        at org.kohsuke.asm5.ClassReader.accept(ClassReader.java:693)
        at org.kohsuke.asm5.ClassReader.accept(ClassReader.java:506)
        at org.jenkinsci.bytecode.Transformer.transform(Transformer.java:113)
        at hudson.ClassicPluginStrategy$AntClassLoader2.defineClassFromData(ClassicPluginStrategy.java:800)
        at jenkins.util.AntClassLoader.getClassFromStream(AntClassLoader.java:1310)
        at jenkins.util.AntClassLoader.findClassInComponents(AntClassLoader.java:1366)
        at jenkins.util.AntClassLoader.findClass(AntClassLoader.java:1326)
        at jenkins.util.AntClassLoader.loadClass(AntClassLoader.java:1079)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
        at org.jenkinsci.jruby.RubyClassConverter.<init>(RubyClassConverter.java:12)
        at org.jenkinsci.jruby.JRubyXStream.register(JRubyXStream.java:25)
        at ruby.RubyRuntimePlugin.initRubyXStreams(RubyRuntimePlugin.java:44)
        at ruby.RubyRuntimePlugin.start(RubyRuntimePlugin.java:28)
        at hudson.ClassicPluginStrategy.startPlugin(ClassicPluginStrategy.java:449)
        at hudson.ClassicPluginStrategy.load(ClassicPluginStrategy.java:438)
        ... 9 more