Question

I’m having this exception,

 @6agjdofnm
Internal Server Error (500) for request GET /

Oops: UnsupportedClassVersionError
An unexpected error occured caused by exception UnsupportedClassVersionError: DocViewerPlugin : Unsupported major.minor version 51.0

play.exceptions.UnexpectedException: Unexpected Error
    at play.Invoker$Invocation.onException(Invoker.java:232)
    at play.Invoker$Invocation.run(Invoker.java:273)
    at Invocation.HTTP Request(Play!)
Caused by: java.lang.UnsupportedClassVersionError: DocViewerPlugin : Unsupported major.minor version 51.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:634)
    at play.classloading.ApplicationClassloader.loadApplicationClass(ApplicationClassloader.java:148)
    at play.classloading.ApplicationClassloader.loadClass(ApplicationClassloader.java:84)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
    at play.plugins.PluginCollection.reloadApplicationPlugins(PluginCollection.java:141)
    at play.Play.start(Play.java:440)
    at play.Play.detectChanges(Play.java:599)
    at play.Invoker$Invocation.init(Invoker.java:186)
    ... 1 more

when i activated my index.html page. Every thing seems to be right dont know why this exception occur. I’m using play-1.2.3

Answer 1

Your a compiling your source code with a higher java version than you are using at runtime.

Example:

compilation with 1.6, but runtime JRE 1.5

You have to change the eclipse launch configuration and use a higher Java Version or you can change the default runtime version in the eclipse preference page “Java-Installed JREs”