How to use

CollectionCallback

in

sockslib.utils.mongo

public <T> T execute(String collectionName, CollectionCallback<T> callback) {
  MongoDatabase database = null;
  if (mongoClient == null) {
    mongoClient = getConnectedClient();
  }
  return callback.doInCollection(
      mongoClient.getDatabase(databaseName).getCollection(collectionName));
}

public <T> T execute(String collectionName, CollectionCallback<T> callback) {
 MongoDatabase database = null;
 if (mongoClient == null) {
  mongoClient = getConnectedClient();
 }
 return callback.doInCollection(
   mongoClient.getDatabase(databaseName).getCollection(collectionName));
}

/**
 * Connect MongoDB and call callback, close connection at last.
 *
 * @param collectionName Collection name.
 * @param callback       Callback
 * @param <T>            The type of value which you want to return.
 * @return The value which callback returned.
 */
public <T> T connect(String collectionName, CollectionCallback<T> callback) {
  MongoClient client = null;
  T t = null;
  try {
    client = getConnectedClient();
    MongoDatabase database = client.getDatabase(databaseName);
    MongoCollection<Document> collection = database.getCollection(collectionName);
    t = callback.doInCollection(collection);
  } finally {
    if (client != null) {
      client.close();
    }
  }
  return t;
}

/**
 * Connect MongoDB and call callback, close connection at last.
 *
 * @param collectionName Collection name.
 * @param callback       Callback
 * @param <T>            The type of value which you want to return.
 * @return The value which callback returned.
 */
public <T> T connect(String collectionName, CollectionCallback<T> callback) {
 MongoClient client = null;
 T t = null;
 try {
  client = getConnectedClient();
  MongoDatabase database = client.getDatabase(databaseName);
  MongoCollection<Document> collection = database.getCollection(collectionName);
  t = callback.doInCollection(collection);
 } finally {
  if (client != null) {
   client.close();
  }
 }
 return t;
}