private Map assembleChunks()

in evcache-core/src/main/java/com/netflix/evcache/pool/EVCacheClient.java [570:664]
88 lines of code
24 McCabe index (conditional complexity)

    private <T> Map<String, T> assembleChunks(Collection<String> keyList, Transcoder<T> tc, boolean hasZF) {
        final List<String> firstKeys = new ArrayList<>();
        for (String key : keyList) {
            firstKeys.add(key);
            firstKeys.add(key + "_00");
        }
        try {
            final Map<String, CachedData> metadataMap = evcacheMemcachedClient.asyncGetBulk(firstKeys, chunkingTranscoder, null)
                    .getSome(bulkReadTimeout.get(), TimeUnit.MILLISECONDS, false, false);
            if (metadataMap == null) return null;

            final Map<String, T> returnMap = new HashMap<>(keyList.size() * 2);
            for (String key : keyList) {
                if (metadataMap.containsKey(key)) {
                    CachedData val = metadataMap.remove(key);
                    returnMap.put(key, tc.decode(val));
                }
            }

            final List<String> allKeys = new ArrayList<>();
            final Map<ChunkInfo, SimpleEntry<List<String>, byte[]>> responseMap = new HashMap<>();
            for (Entry<String, CachedData> entry : metadataMap.entrySet()) {
                final String firstKey = entry.getKey();
                final String metadata = (String) decodingTranscoder.decode(entry.getValue());
                if (metadata == null) continue;
                final ChunkInfo ci = getChunkInfo(firstKey, metadata);
                if (ci != null) {
                    final List<String> ciKeys = new ArrayList<>();

                    for (int i = 1; i < ci.getChunks(); i++) {
                        final String prefix = (i < 10) ? "0" : "";
                        final String _key = ci.getKey() + "_" + prefix + i;
                        allKeys.add(_key);
                        ciKeys.add(_key);
                    }

                    final byte[] data = new byte[(ci.getChunks() - 2) * ci.getChunkSize() + ci.getLastChunk()];
                    responseMap.put(ci, new SimpleEntry<>(ciKeys, data));
                }
            }

            final Map<String, CachedData> dataMap = evcacheMemcachedClient.asyncGetBulk(allKeys, chunkingTranscoder, null)
                    .getSome(bulkReadTimeout.get(), TimeUnit.MILLISECONDS, false, false);

            for (Entry<ChunkInfo, SimpleEntry<List<String>, byte[]>> entry : responseMap.entrySet()) {
                final ChunkInfo ci = entry.getKey();
                final SimpleEntry<List<String>, byte[]> pair = entry.getValue();
                final List<String> ciKeys = pair.getKey();
                byte[] data = pair.getValue();
                int index = 0;
                for (int i = 0; i < ciKeys.size(); i++) {
                    final String _key = ciKeys.get(i);
                    final CachedData cd = dataMap.get(_key);
                    if (log.isDebugEnabled()) log.debug("Chunk Key " + _key + "; Value : " + cd);
                    if (cd == null) continue;
                    final byte[] val = cd.getData();

                    if (val == null) {
                        data = null;
                        break;
                    }
                    final int len = (i == ciKeys.size() - 1) ? ((ci.getLastChunk() == 0 || ci.getLastChunk() > ci
                            .getChunkSize()) ? ci.getChunkSize() : ci.getLastChunk())
                            : val.length;
                    try {
                        System.arraycopy(val, 0, data, index, len);
                    } catch (Exception e) {
                        StringBuilder sb = new StringBuilder();
                        sb.append("ArrayCopyError - Key : " + _key + "; final data Size : " + data.length
                                + "; copy array size : " + len + "; val size : " + val.length
                                + "; key index : " + i + "; copy from : " + index + "; ChunkInfo : " + ci + "\n");
                        for (int j = 0; j < ciKeys.size(); j++) {
                            final String skey = ciKeys.get(j);
                            final byte[] sval = dataMap.get(skey).getData();
                            sb.append(skey + "=" + sval.length + "\n");
                        }
                        if (log.isWarnEnabled()) log.warn(sb.toString(), e);
                        throw e;
                    }
                    index += val.length;
                }
                final boolean checksumPass = checkCRCChecksum(data, ci, hasZF);
                if (data != null && checksumPass) {
                    final CachedData cd = new CachedData(ci.getFlags(), data, Integer.MAX_VALUE);
                    returnMap.put(ci.getKey(), tc.decode(cd));
                } else {
                    returnMap.put(ci.getKey(), null);
                }
            }
            return returnMap;
        } catch (Exception e) {
            log.error(e.getMessage(), e);
        }
        return null;
    }