public HiveSamlRelayStateInfo getRelayStateInfo(String relayStateId)
      throws HttpSamlAuthenticationException {
    HiveSamlRelayStateInfo relayStateInfo = relayStateCache.getIfPresent(relayStateId);
    if (relayStateInfo == null) {
      throw new HttpSamlAuthenticationException(
          "Invalid value of relay state received: " + relayStateId);
    }
    return relayStateInfo;
  }
Given a RelayStateIdentifier, return the {@link HiveSamlRelayStateInfo}
@param relayStateId
@return
@throws HttpSamlAuthenticationException if there is no {@link HiveSamlRelayStateInfo}
for the given relayStateIdentifier. This could happen if there is a unknown relay
state from the request or if the IDP responded too late and the cached RelayState
was evicted.
service/src/java/org/apache/hive/service/auth/saml/HiveSamlRelayStateStore.java