This is one is a blazing fast tip, did you ever stumble in a .jks (keystore) file from a client while trying to submit to Google Play that precious app you just finished? Well sometimes, or always…. who knows, your client simply does not have the alias name and has a list of possible passwords.
One tip that should make things easier is listing aliases inside the .jks, just try the following keytool -list -keystore keystore_name.jks in a terminal, something like this will popout
Keystore type: JKS
Keystore provider: SUN
Your keystore contains 1 entry
alias name, DAY-MONTH-YEAR, PrivateKeyEntry,
Certificate fingerprint (SHA1): SHA_VALUE