code: static List<InetSocketAddress> tryResolveHosts(final List<InetSocketAddress> hosts) {
          List<InetSocketAddress> resolvableHosts = new ArrayList<InetSocketAddress>();
          for (InetSocketAddress node : hosts) {
              try {
                  node.getAddress().getHostAddress();
                  resolvableHosts.add(node);
              } catch (NullPointerException ex) {
                  LOGGER.error("Unable to resolve address " + node.toString());
              }
          }
          return resolvableHosts;
      }
docs: Make sure the address is resolvable