This is issue recently occurred at work while I was working on the migration to IBM WAS 8.5. The migration was from WAS 7.0 and JDK 1.6 to WAS 8.5 JDK1.8. The issue rises if you compile the project with a different(in my case lower) JDK version that the installed on the server. To resolve this issue compile the project with the proper java version.
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