java.lang.LinkageError Error in Class Loading

I have some problem with my JSystem/Java/Eclipse enviromment.

I get this error and i don't understand what is wrong:

java.lang.LinkageError: loader constraint violation: loader (instance of jsystem/runner/loader/ExtendsTestCaseClassLoader) previously initiated l开发者_运维技巧oading for a different type with name "org/w3c/dom/Document"

I would like know if someone have had a similar issues, I don't think my enviromment is very important for solve it, if I will understand what's happened "undergound" I hope to solve problem myself.

Thanks a lot in advance.

I think this happened for me when I included a library twice.

Please check the below URL

java.lang.LinkageError: loader constraint violation

For me it was a version of dependency, when i increased version it fixed