Method call

src/RegionClient.java:626–655

Handles the response of #helloRpc. @return null when it re-tried for a version mismatch. A version object if it was successful. @throws an exception If there was an error that we cannot retry. It includes ServerNotRunningYetExceptio, and NotServingRegionException.

(final Object response)

     * includes ServerNotRunningYetExceptio, and NotServingRegionException.
     */
    public Long call(final Object response) throws Exception {
      if (response instanceof VersionMismatchException) {
        if (server_version == SERVER_VERSION_UNKNWON) {
          // If we get here, it's because we tried to handshake with a server
          // running HBase 0.92 or above, but using a pre-0.92 handshake.  So
          // we know we have to handshake differently.
          server_version = SERVER_VERSION_092_OR_ABOVE;
          helloRpc(chan, header092());
        } else {
          // We get here if the server refused our 0.92-style handshake.  This
          // must be a future version of HBase that broke compatibility again,
          // and we don't know how to talk to it, so give up here.
          throw (VersionMismatchException) response;
        }
        return null;
      } else if (!(response instanceof Long)) {
        if (response instanceof Exception) {  // If it's already an exception,
          throw (Exception) response;         // just re-throw it as-is.
        }
        throw new InvalidResponseException(Long.class, response);
      }
      final Long version = (Long) response;
      final long v = version;
      if (v <= 0 || v > Byte.MAX_VALUE) {
        throw new InvalidResponseException("getProtocolVersion returned a "
          + (v <= 0 ? "negative" : "too large") + " value", version);
      }
      becomeReady(chan, (byte) v);
      return version;
    }

    public String toString() {
      return "handle getProtocolVersion response on " + chan;