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If I have a classes A_1, … A_m extending a class B, then the size of an object of A_i is at least the size of an object of B.
If I now declare an array
B collB[] = new B[1];
then how much space is allocated?
Thank you
That’s creating an array with one element. It’ll probably be about 20 bytes, and will vary depending on the JVM you’re using (e.g. 32-bit vs 64-bit).
It won’t vary at all by the number of fields in
B, orA, or anything like that – because you’re not actually creating any instances ofB. You’re only creating an array, whose sole element will be a null reference initially.