I have a clue of what serialVersionUID is for, and in as far as I don't I can look it up. But it can be a private variable that's not used inside the class. Is there some construct or so behind that? Are there other examples of private variables / methods that are not used inside the same class? Can I access private variables in Java without getters from a class that's not an inner class, like serialization does?
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1you can use [reflection](http://stackoverflow.com/questions/37628/what-is-reflection-and-why-is-it-useful) – BeyelerStudios Jul 08 '15 at 12:29
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downvoter please clarify. – Albert Hendriks Jul 08 '15 at 12:33
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1No, please close. That's what I was looking for. – Albert Hendriks Jul 08 '15 at 12:37
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You can access those values, and manipulate them via Reflection. By this mechanism you can check fields and invoke methods.
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This field is being read by Java virtual machine which can do whatever it wants with your program including reading the private fields. Note that serialization-related methods like writeObject can also be private, but this is not a problem for JVM either.
You can also access private fields/methods via reflection or java.lang.invoke API (however SecurityManager may prevent you from doing this). In Oracle JDK/Open JDK there's also non-documented sun.misc.Unsafe API which allows you to do many ughm unsafe things including even reading the raw data from objects.
Tagir Valeev
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Using java.lang.reflect.Member.setAccessible(true) will override any privacy at runtime (not that there is much – the JVM will happily access private fields or methods given their name, see this answer.
