private List getEVCacheClientsForReadExcludingInternal()

in evcache-core/src/main/java/com/netflix/evcache/pool/EVCacheClientPool.java [435:481]
45 lines of code
16 McCabe index (conditional complexity)

    private List<EVCacheClient> getEVCacheClientsForReadExcludingInternal(ServerGroup serverGroupToExclude) {
        if (memcachedReadInstancesByServerGroup == null || memcachedReadInstancesByServerGroup.isEmpty()) {
            if (log.isDebugEnabled()) log.debug("memcachedReadInstancesByServerGroup : " + memcachedReadInstancesByServerGroup);
            if(asyncRefreshExecutor.getQueue().isEmpty()) refreshPool(true, true);
            return Collections.<EVCacheClient> emptyList();
        }
        try {
            if (_retryAcrossAllReplicas.get()) {
                List<EVCacheClient> clients = new ArrayList<EVCacheClient>(memcachedReadInstancesByServerGroup.size() - 1);
                for (Iterator<ServerGroup> itr = memcachedReadInstancesByServerGroup.keySet().iterator(); itr
                        .hasNext();) {
                    final ServerGroup serverGroup = itr.next();
                    if (serverGroup.equals(serverGroupToExclude)) continue;

                    final List<EVCacheClient> clientList = memcachedReadInstancesByServerGroup.get(serverGroup);
                    final EVCacheClient client = selectClient(clientList);
                    if (client != null) clients.add(client);
                }
                return clients;
            } else {
                if(_maxRetries.get() == 1) {
                    final EVCacheClient client = getEVCacheClientForReadExclude(serverGroupToExclude);
                    if (client != null) return Collections.singletonList(client);
                } else {
                    int maxNumberOfPossibleRetries = memcachedReadInstancesByServerGroup.size() - 1;
                    if(maxNumberOfPossibleRetries > _maxRetries.get()) {
                        maxNumberOfPossibleRetries = _maxRetries.get();
                    }
                    final List<EVCacheClient> clients = new ArrayList<EVCacheClient>(_maxRetries.get());
                    for(int i = 0; i < maxNumberOfPossibleRetries; i++) {
                        ServerGroup fallbackServerGroup = memcachedFallbackReadInstances.next(serverGroupToExclude);
                        if (fallbackServerGroup == null ) {
                            return clients;
                        }

                        final List<EVCacheClient> clientList = memcachedReadInstancesByServerGroup.get(fallbackServerGroup);
                        final EVCacheClient client = selectClient(clientList);
                        if (client != null) clients.add(client);
                    }
                    return clients;
                }
            }
        } catch (Throwable t) {
            log.error("Exception trying to get an readable EVCache Instances for zone {}", serverGroupToExclude, t);
        }
        return Collections.<EVCacheClient> emptyList();
    }