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''Martijn Dashorst - Extracted from wicket-user mailing list

Debugging NotSerializableException

If you get a NotSerializableException on a deeply nested class like MyClass$2$1$1, it can be difficult to figure out which part of your code is causing the problem.

Solution: use javap, but be sure to escape the $'s: javap mypackage.MyClass\$2\$1\$1

Gotchas

Empty URL Parameter in CSS Style ( background-image: url(""); )

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