You now have a signed JAR file sCount.jar. The runtime system of the code receiver (Ray) will need to authenticate the signature when the Count application in the signed JAR file tries to read a file and a policy file grants that permission to this signed code.
In order for the runtime system to authenticate the signature, Ray's keystore needs to have the public key corresponding to the private key used to generate the signature. You supply this by sending Ray a copy of the certificate authenticating the public key. Copy that certificate from the keystore examplestore to a file named Example.cer via the following:
keytool -export -keystore examplestore -alias signFiles -file Example.cer
You will be prompted for the store password.