Resolution:
java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:585)
        at com.tibco.administrator.wizard.progress.Trampoline.invoke(Trampoline.java:96)
        at com.tibco.administrator.wizard.progress.BusyWait.run(BusyWait.java:267)
        at java.lang.Thread.run(Thread.java:595)
Caused by: java.lang.UnsupportedClassVersionError: Bad version number in .class file
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
        at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:164)
        at com.tibco.administrator.domain.DomainConfiguration.a(DomainConfiguration.java:1646)
        at com.tibco.administrator.domain.DomainConfiguration.createDbDomainFiles(DomainConfiguration.java:1155)
        at com.tibco.administrator.domain.DomainConfiguration.joinDomain(DomainConfiguration.java:1047)
        at com.tibco.administrator.du.task.addmachine.JoinDomainTask.joinDomain(JoinDomainTask.java:242)
        at com.tibco.administrator.du.task.addmachine.JoinDomainTask.execute(JoinDomainTask.java:206)
        ... 7 more

This error is caused by conflicting jar files ie., class files compiled with a higher version of JDK and these class files are being executed/referenced by a lower JDK version (E.g: Compiled with JDK 1.6 and run on JDK 1.5).

Errors when attempting to add a machine to a domain - java.lang.UnsupportedClassVersionError: Bad version number in .class file