RequestSecurityTokenResponseCollection collection = (RequestSecurityTokenResponseCollection) baseResponse;
RequestSecurityTokenResponse response = collection.getRequestSecurityTokenResponses().get(0);
RequestedProofTokenType proofToken = response.getRequestedProofToken();
assertNotNull("Unexpected null proof token", proofToken);
assertTrue(proofToken.getAny().get(0) instanceof ComputedKeyType);
ComputedKeyType computedKey = (ComputedKeyType) proofToken.getAny().get(0);
assertEquals("Unexpected computed key algorithm", WSTrustConstants.CK_PSHA1, computedKey.getAlgorithm());
// server entropy must have been included in the response to allow reconstruction of the computed key.
EntropyType serverEntropy = response.getEntropy();
assertNotNull("Unexpected null server entropy");
assertEquals("Invalid number of elements in server entropy", 1, serverEntropy.getAny().size());