Possible race condition in RetryInvocationHandler

  while (true) {
      // The number of times this invocation handler has ever been failed over,
      // before this method invocation attempt. Used to prevent concurrent
      // failed method invocations from triggering multiple failover attempts.
      long invocationAttemptFailoverCount;
      synchronized (proxyProvider) {
        invocationAttemptFailoverCount = proxyProviderFailoverCount;
      }
      ......
      if (action.action == RetryAction.RetryDecision.FAILOVER_AND_RETRY) {
            // Make sure that concurrent failed method invocations only cause a
            // single actual fail over.
            synchronized (proxyProvider) {
              if (invocationAttemptFailoverCount == proxyProviderFailoverCount) {
                proxyProvider.performFailover(currentProxy.proxy);
                proxyProviderFailoverCount++;
                currentProxy = proxyProvider.getProxy();
              } else {
                LOG.warn("A failover has occurred since the start of this method"
                    + " invocation attempt.");
              }
            }
            invocationFailoverCount++;
          }
     ......