Compile-time checking for Serializable

Hi,
For an object to be Serialized it must implement the Serializable interface. If any of the objects it stores as instance variables do not implement this interface then run-time exceptions will be thrown. Why can't there be a compile-time check for this? It seems fairly simple to me... Also, why don't the writeObject methods only accept objects that are Serializable? Just changing the method signature to public void writeObject(Serializable obj) throws... should be enough if compile-time checking were available.
Am I being really stupid or are Sun?
Dan.

It would be impossible to reasonably check at compile time, because what if you had a variable of type Object? At runtime it might work because anything could be in there, but if you check at compile time, it would have to fail, because the compiler can't gurantee that the value will be serializable. Also, a non-serializable field wouldn't cause a problem at runtime if it's null, which is another condition the compiler cannot check.

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Message was edited by:
developer_jbs

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Last edited by blackout23 (2011-12-30 22:42:21)

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