Java Security

I use AES key encrypt a file because RSA can't be use for encrypting long file.and use RSA encrypt the AES key.
but hwo to implement.
first i do like this.

 javax.crypto.KeyGenerator keygen = javax.crypto.KeyGenerator
                        .getInstance("AES");
                SecureRandom random = new SecureRandom();
                keygen.init(random);
                this.secretKey = keygen.generateKey();
Encriptor.encripteRSA(secretKey.getEncoded(),this.privateKey,CryAESFile);

the method Encriptor.encripteRSA 's job is use RSA encrypt the secretKey.getEncoded.but it does't work when i get back . complier tell me it is not a valid AES key.so what can i do.
thanks for any help.