java实现mongodb的数据库连接池

MongoDB是介于关系数据库和非关系数据库之间的一种产品，文件的存储格式为BSON（一种JSON的扩展）,这里就主要介绍Java通过使用mongo-2.7.3.jar包实现mongodb连接池，具体的java代码实现如下：

数据库连接池配置参数：

/**
*@Description: mongo连接池配置文件
*/
package cn.lulei.mongo.pool;

public class MongoConfig {

private static String userName;//用户名
private static String pwd;//密码
private static String[] host;//主机地址
private static int[] port;//端口地址
private static String dbName;//数据库名
private static int connectionsPerHost = 20;//每台主机最大连接数
private static int threadsAllowedToBlockForConnectionMultiplier = 10;//线程队列数
private static boolean authentication = false;//是否需要身份验证

public static String getUserName() {
 return userName;
}
public static void setUserName(String userName) {
 MongoConfig.userName = userName;
}
public static String getPwd() {
 return pwd;
}
public static void setPwd(String pwd) {
 MongoConfig.pwd = pwd;
}
public static String[] getHost() {
 return host;
}
public static void setHost(String[] host) {
 MongoConfig.host = host;
}
public static int[] getPort() {
 return port;
}
public static void setPort(int[] port) {
 MongoConfig.port = port;
}
public static String getDbName() {
 return dbName;
}
public static void setDbName(String dbName) {
 MongoConfig.dbName = dbName;
}
public static int getConnectionsPerHost() {
 return connectionsPerHost;
}
public static void setConnectionsPerHost(int connectionsPerHost) {
 MongoConfig.connectionsPerHost = connectionsPerHost;
}
public static int getThreadsAllowedToBlockForConnectionMultiplier() {
 return threadsAllowedToBlockForConnectionMultiplier;
}
public static void setThreadsAllowedToBlockForConnectionMultiplier(
  int threadsAllowedToBlockForConnectionMultiplier) {
 MongoConfig.threadsAllowedToBlockForConnectionMultiplier = threadsAllowedToBlockForConnectionMultiplier;
}
public static boolean isAuthentication() {
 return authentication;
}
public static void setAuthentication(boolean authentication) {
 MongoConfig.authentication = authentication;
}
}

数据库连接池管理类：

/**
*@Description: mongo数据库连接池管理类
*/
package cn.lulei.mongo.pool;

import java.util.ArrayList;
import java.util.List;

import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.Mongo;
import com.mongodb.MongoOptions;
import com.mongodb.ReadPreference;
import com.mongodb.ServerAddress;

public class MongoManager {

private static Mongo mongo;
private DB db;

static{
 init();
}

/**
* @param dbName
* @param userName
* @param pwd
* 实例化dbName一个DB
 */
public MongoManager(String dbName, String userName, String pwd) {
 if (dbName == null || "".equals(dbName)) {
  throw new NumberFormatException("dbName is null");
 }
 db = mongo.getDB(dbName);
 if(MongoConfig.isAuthentication() && !db.isAuthenticated()){
  if (userName == null || "".equals(userName)) {
   throw new NumberFormatException("userName is null");
  }
  if (pwd == null || "".equals(pwd)) {
   throw new NumberFormatException("pwd is null");
  }
  db.authenticate(userName, pwd.toCharArray());
 }
}

/**
 * 使用配置参数实例化
 */
public MongoManager() {
 this(MongoConfig.getDbName(), MongoConfig.getUserName(), MongoConfig.getPwd());
}

/**
 * @param tableName
 * @return
 * @Description: 获取表tableName的链接DBCollection
 */
public DBCollection getDBCollection(String tableName) {
 return db.getCollection(tableName);
}

/**
 * @Description: mongo连接池初始化
 */
private static void init() {
 if (MongoConfig.getHost() == null || MongoConfig.getHost().length == 0) {
  throw new NumberFormatException("host is null");
 }
 if (MongoConfig.getPort() == null || MongoConfig.getPort().length == 0) {
  throw new NumberFormatException("port is null");
 }
 if (MongoConfig.getHost().length != MongoConfig.getPort().length) {
  throw new NumberFormatException("host's length is not equals port's length");
 }
 try {
  //服务列表
  List<ServerAddress> replicaSetSeeds = new ArrayList<ServerAddress>();
  for (int i = 0; i < MongoConfig.getHost().length; i++) {
   replicaSetSeeds.add(new ServerAddress(MongoConfig.getHost()[i], MongoConfig.getPort()[i]));
  }
  //连接池参数设置
  MongoOptions options = new MongoOptions();
  options.connectionsPerHost = MongoConfig.getConnectionsPerHost();
  options.threadsAllowedToBlockForConnectionMultiplier = MongoConfig.getThreadsAllowedToBlockForConnectionMultiplier();
  mongo = new Mongo(replicaSetSeeds, options);
  //从服务器可读
  mongo.setReadPreference(ReadPreference.SECONDARY);
 } catch (Exception e){
  e.printStackTrace();
 }
}
}

下面通过一个简单的测试类，来看下如何使用这个连接池~

/**
*@Description:mongo测试
*/
package cn.lulei.mongo.test;

import cn.lulei.mongo.pool.MongoConfig;
import cn.lulei.mongo.pool.MongoManager;

public class Test {

public static void main(String[] args) {
 // TODO Auto-generated method stub
 String[] host = {"127.0.0.1"};
 int[] port = {27001};
 MongoConfig.setHost(host);
 MongoConfig.setPort(port);
 MongoConfig.setDbName("novel");
 MongoManager mongoManager = new MongoManager();
 mongoManager.getDBCollection("chapter");
}

}

在使用上述管理类时，只需要初始化MongoConfig类即可。对类MongoManager的实例话，既可以使用MongoConfig的配置也可以自己通过参数来设置，每次获取DBCollection 时，只需要调用getDBCollection(String tableName)方法即可。