code: public boolean isHostProxyable(String host) {
          return getProxyHost() != null
                  && getProxyPort() > 0
                  && (nonProxyPattern == null || !nonProxyPattern.matcher(host)
                          .matches());
      }
docs: Checks whether a proxy has been configured and the given host is not in
  the nonProxyHost list or the nonProxyList is empty.
  
  @param host
  the host to be matched
  @return true if the host satifies the above stated condition, otherwise
  false.