cdm/src/main/java/thredds/inventory/CollectionManagerAbstract.java
public void putMetadata(MFile file, String key, byte[] value) {
    if (store == null) initMM();
    if (store != null) store.put(file.getPath()+"#"+key, value);
  }
public void putMetadata(MFile file, String key, byte[] value) {
    if (store == null) initMM();
    if (store != null) store.put(file.getPath()+"#"+key, value);
  }
/* clean up deleted files in metadata manager
protected void deleteOld(Map<String, MFile> newMap) {
if (store == null && enableMetadataManager) initMM();
if (store != null) store.delete(newMap);
}