Question: Why am I am receiving an SSLHandshakeException when making a REST Service Call?        

You will receive this exception when trying to make a request to a target server using an SSL connection when the certificate is not in your JRE's list of trusted certificate authorities(CA's). To correct this you must add the certificate to your JRE's list of trusted CA's.     See the Adding Security Certificates to a Deployment Server for Outbound Requests article for more information.