/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.felix.useradmin.mongodb;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicReference;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.Mongo;
import com.mongodb.MongoException;
import com.mongodb.ServerAddress;
/**
* Provides a simple facade for accessing MongoDB.
*/
final class MongoDB {
private final List<ServerAddress> m_servers;
private final String m_dbName;
private final String m_collectionName;
private final AtomicReference<Mongo> m_mongoRef;
/**
* Creates a new {@link MongoDB} instance.
*
* @param serverNames the space separated list of Mongo servers, cannot be <code>null</code> or empty;
* @param dbName the name of the MongoDB to connect to, cannot be <code>null</code> or empty;
* @param collectionName the name of the collection to use, cannot be <code>null</code> or empty.
*/
public MongoDB(String serverNames, String dbName, String collectionName) {
if (serverNames == null || "".equals(serverNames.trim())) {
throw new IllegalArgumentException("ServerNames cannot be null or empty!");
}
if (dbName == null || "".equals(dbName.trim())) {
throw new IllegalArgumentException("DbName cannot be null or empty!");
}
if (collectionName == null || "".equals(collectionName.trim())) {
throw new IllegalArgumentException("CollectionName cannot be null or empty!");
}
m_mongoRef = new AtomicReference<Mongo>();
m_servers = parseServers(serverNames);
m_dbName = dbName;
m_collectionName = collectionName;
}
/**
* Parses the space separated list of server names.
*
* @param serverNames the server names, cannot be <code>null</code>.
* @return a list of {@link ServerAddress}es to connect to, never <code>null</code>.
* @throws IllegalArgumentException in case the given server names was invalid.
*/
private static List<ServerAddress> parseServers(String serverNames) {
String[] parts = serverNames.split("\\s+");
List<ServerAddress> servers = new ArrayList<ServerAddress>();
for (int i = 0; i < parts.length; i++) {
String part = parts[i];
try {
int colonPos = part.indexOf(":");
if (colonPos > 0 && (colonPos < part.length() - 1)) {
String name = part.substring(0, colonPos);
String portStr = part.substring(colonPos + 1);
servers.add(new ServerAddress(name, Integer.valueOf(portStr)));
}
}
catch (NumberFormatException e) {
throw new IllegalArgumentException("Illegal port number in: " + part);
}
catch (UnknownHostException e) {
throw new IllegalArgumentException("Unknown host: " + part);
}
}
if (servers.isEmpty()) {
throw new IllegalArgumentException("No (valid) servers defined!");
}
return servers;
}
/**
* Connects to the MongoDB with the supplied credentials.
*
* @param userName the optional user name to use;
* @param password the optional password to use.
* @return <code>true</code> if the connection was succesful, <code>false</code> otherwise.
*/
public boolean connect(String userName, String password) {
Mongo newMongo = new Mongo(m_servers);
Mongo oldMongo;
do {
oldMongo = m_mongoRef.get();
} while (!m_mongoRef.compareAndSet(oldMongo, newMongo));
DB db = newMongo.getDB(m_dbName);
if ((userName != null) && (password != null)) {
if (!db.authenticate(userName, password.toCharArray())) {
return false;
}
}
return true;
}
/**
* Returns the database collection to work in.
*
* @return the {@link DBCollection}, never <code>null</code>.
* @throws MongoException in case no connection to Mongo exists.
*/
public DBCollection getCollection() {
Mongo mongo = m_mongoRef.get();
if (mongo == null) {
throw new MongoException("Not connected to MongoDB!");
}
DB db = mongo.getDB(m_dbName);
return db.getCollection(m_collectionName);
}
/**
* Disconnects from the MongoDB.
*/
public void disconnect() {
Mongo mongo = m_mongoRef.get();
if (mongo != null) {
try {
mongo.close();
} finally {
m_mongoRef.compareAndSet(mongo, null);
}
}
}
}