What is the difference between ECKey in bitcoinj and CKey in bitcoin-qt ?

[IloveAnonCoin]

I have tried to see the difference between two class, but still think it is almost the same.

[Nicolas Dorier]

An ECKey can be both, public or private, this is a thin layer about the EC DSA operations.
CKey is a real private key, one layer about ECKey, and can't represent a public key.
If my memory is good, CPubKey also encapsulate an CECKey.

At least, this is how I implemented it in NBitcoin, and I was inspired by core + BitcoinJ, so it should be what I tell you.