@Override
    public SegmentOutputStreamProvider getSegmentOutputStreamProvider(final String streamTypeName) {
        return outputStreamMap.computeIfAbsent(streamTypeName, k -> {
            final FsTarget target = getChild(k);
            if (target == null) {
                return null;
            }
            return new SegmentOutputStreamProvider(target, k);
        });
    }
Creates a new file system stream target.

@return A new file system target.
stroom-data/stroom-data-store-impl-fs/src/main/java/stroom/data/store/impl/fs/FsTarget.java