I know there a limitations with RestAssured and self signed certificates. In the hopes of getting an enhancement for that sooner rather than later I've created and attached a simple test that demonstrates at least one way to setup HttpClient+Jetty to get this to work. Ideally I think that RestAssured would support the specification of the keystore, truststore and X509HostnameVerifier as both a request and "globally".
given()
.keystore( "/pathToJksKeyStoreInClassPath", <password> )
.truststore( "/pathToJksTrustStoreInClassPath", <password> )
.hostNameVerifier( SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER )
and
RestAssured.keystore( "/pathToJksKeyStoreInClassPath", <password> );
RestAssured.truststore( "/pathToJksTrustStoreInClassPath", <password> );
RestAssured.hostNameVerifier( SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER );