private boolean isProxyInInitializationMode(CacheClientProxy proxy) {
    return _initClientProxies.containsKey(proxy.getProxyID());
  }
Adds a new {@code CacheClientProxy} to the list of known client proxies

@param proxy The {@code CacheClientProxy} to add
geode-core/src/main/java/org/apache/geode/internal/cache/tier/sockets/CacheClientNotifier.java