Casting to void* removes all type safety. If you use reinterpret_cast or static_cast to cast from a pointer type to void* and back to the same pointer type, you are actually guaranteed by the standard that the result will be well-defined.
Casting can be used to clearly state that you are calling a child method and not a parent method. So in this case it's always a downcast or more correctly, a narrowing conversion.
Classic casting (something like (Bar)foo in C, used in C++ with reinterpret_cast<>) is when the actual memory contents of a variable are assumed to be a variable of a different type. Type conversion (ie. Boost's lexical_cast<> or other user-defined functions which convert types) is when some logic is performed to actually a variable from one type to another, like integer to a string, where ...
Casting private key to RSACryptoServiceProvider not working Asked 6 years, 11 months ago Modified 4 years, 8 months ago Viewed 19k times
Essentially casting will not change anything in how it works, it does exactly what it says, allocates memory, and casting does not effect it, you get the same memory, and even if you cast it to something else by mistake (and somehow evade compiler errors) C will access it the same way. Edit: Casting has a certain point.
For casting to a class type, it is known exactly how many superclasses there are until you hit java.lang.Object, so the type can be read at a constant offset from the type pointer (actually the first eight in HotSpot).
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