public static Map getOpenShards()

in src/main/java/com/amazonaws/services/kinesis/scaling/StreamScalingUtils.java [293:347]
41 lines of code
9 McCabe index (conditional complexity)

	public static Map<String, ShardHashInfo> getOpenShards(KinesisClient kinesisClient, String streamName,
			SortOrder sortOrder, String lastShardId) throws Exception {
		Collection<String> openShardNames = new ArrayList<>();
		Map<String, ShardHashInfo> shardMap = new LinkedHashMap<>();

		// load all the open shards on the Stream and sort if required
		for (Shard shard : listShards(kinesisClient, streamName, lastShardId)) {
			openShardNames.add(shard.shardId());
			shardMap.put(shard.shardId(), new ShardHashInfo(streamName, shard));

			// remove this Shard's parents from the set of active shards - they
			// are now closed and cannot be modified or written to
			if (shard.parentShardId() != null) {
				openShardNames.remove(shard.parentShardId());
				shardMap.remove(shard.parentShardId());
			}
			if (shard.adjacentParentShardId() != null) {
				openShardNames.remove(shard.adjacentParentShardId());
				shardMap.remove(shard.adjacentParentShardId());
			}
		}

		// create a List of Open shards for sorting
		List<Shard> sortShards = new ArrayList<>();
		for (String s : openShardNames) {
			// paranoid null check in case we get a null map entry
			if (s != null) {
				sortShards.add(shardMap.get(s).getShard());
			}
		}

		if (sortOrder.equals(SortOrder.ASCENDING)) {
			// sort the list into lowest start hash order
			Collections.sort(sortShards, new Comparator<Shard>() {
				public int compare(Shard o1, Shard o2) {
					return compareShardsByStartHash(o1, o2);
				}
			});
		} else if (sortOrder.equals(SortOrder.DESCENDING)) {
			// sort the list into highest start hash order
			Collections.sort(sortShards, new Comparator<Shard>() {
				public int compare(Shard o1, Shard o2) {
					return compareShardsByStartHash(o1, o2) * -1;
				}
			});
		} // else we were supplied a NONE sort order so no sorting

		// build the Shard map into the correct order
		shardMap.clear();
		for (Shard s : sortShards) {
			shardMap.put(s.shardId(), new ShardHashInfo(streamName, s));
		}

		return shardMap;
	}