private void unlock(final Meta meta, final AttributeMap attributeMap) {
        if (Status.UNLOCKED.equals(meta.getStatus())) {
            throw new IllegalStateException("Attempt to unlock data that is already unlocked");
        }

        // Write the meta data
        if (!attributeMap.isEmpty()) {
            try {
                metaService.addAttributes(meta, attributeMap);
            } catch (final RuntimeException e) {
                LOGGER.error(() -> "unlock() - Failed to persist attributes in new transaction... will ignore");
            }
        }

        LOGGER.debug(() -> "unlock() " + meta);
        this.meta = metaService.updateStatus(meta, Status.LOCKED, Status.UNLOCKED);
    }
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