code: public void reloadCollection(String collectionName) {
      CollectionMetaData cmd = cmdMap.get(collectionName);
      cmd.getCollectionLock().writeLock().lock();
      try {
        File collectionFile = fileObjectsRef.get().get(collectionName);
        if(null == collectionFile) {
          // Lets create a file now
          collectionFile = new File(dbConfig.getDbFilesLocation(), collectionName + ".json");
          if(!collectionFile.exists()) {
            throw new InvalidJsonDbApiUsageException("Collection by name '" + collectionName + "' cannot be found at " + collectionFile.getAbsolutePath());
          }
          Map<String, File> fileObjectMap = fileObjectsRef.get();
          Map<String, File> newFileObjectmap = new ConcurrentHashMap<String, File>(fileObjectMap);
          newFileObjectmap.put(collectionName, collectionFile);
          fileObjectsRef.set(newFileObjectmap);
        }
        if (null != cmd && null != collectionFile) {
          Map<Object, ?> collection = loadCollection(collectionFile, collectionName, cmd);
          if (null != collection) {
            JXPathContext newContext = JXPathContext.newContext(collection.values());
            contextsRef.get().put(collectionName, newContext);
            collectionsRef.get().put(collectionName, collection);
          } else {
            //Since this is a reload attempt its possible the .json files have disappeared in the interim a very rare thing
            contextsRef.get().remove(collectionName);
            collectionsRef.get().remove(collectionName);
          }
        }
      } finally {
        cmd.getCollectionLock().writeLock().unlock();
      }
    }
docs: /* (non-Javadoc)
  @see io.jsondb.JsonDBOperations#reloadCollection(java.lang.String)