NoSql之MongoDB实现数据库数据操作

1、创建唯一数据库实例DB

package com.boonya.mongo;
import java.net.UnknownHostException;
import java.util.Arrays;
import com.mongodb.DB;
import com.mongodb.MongoClient;
import com.mongodb.ServerAddress;


public class DBConnection {

private DBConnection(){}

private static String  userName="boonya";
private static char [] password="boonya".toCharArray();
private static  DB db=null;

/**
 * mongoClient = new MongoClient();
         * // or
         * mongoClient = new MongoClient( "localhost" );
         * // or
         * mongoClient = new MongoClient( "localhost" , 27017 );
         * // or, to connect to a replica set, supply a seed list of members
 * @return
 */
public synchronized static DB getInstance(){
        if(db==null){
    MongoClient mongoClient=null;
    try {
    mongoClient = new MongoClient(Arrays.asList(new ServerAddress("localhost", 27017),
    new ServerAddress("localhost", 27018),
    new ServerAddress("localhost", 27019)));
    } catch (UnknownHostException e) {
    e.printStackTrace();
    }
    db = mongoClient.getDB("mydb");
    boolean auth = db.authenticate(userName,password);
            if(!auth){                      //the authentication is invalid
            return null;
            }
        }
return db;
}

}

2、创建CRUD操作工具类

package com.boonya.mongo.optimize;
import java.net.UnknownHostException;
import com.boonya.mongo.utils.ConstantUtils;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.Mongo;
import com.mongodb.MongoException;
import com.mongodb.MongoOptions;


public class MongDbCRUD {

private static Mongo mongo = null;
private static DB db;
private static DBCollection table;

private static MongDbCRUD instace;

public static synchronized MongDbCRUD getInstance(){
if(instace==null||mongo==null||db==null||table==null){
instace = new MongDbCRUD();
}
return instace;
}

public MongDbCRUD(){
String host = ConstantUtils.getValue("mongo.host").toString();
int port = Integer.parseInt(ConstantUtils.getValue("mongo.port").toString());
String datablease = ConstantUtils.getValue("mongo.datablease").toString();
String tablelename = ConstantUtils.getValue("mongo.table.bound").toString();

try {
mongo = new Mongo(host, port);
// 连接池
MongoOptions opt = mongo.getMongoOptions();
opt.connectionsPerHost =  10  ; //poolsize
opt.threadsAllowedToBlockForConnectionMultiplier =  10 ;

//获取temp DB；如果默认没有创建，mongodb会自动创建
db = mongo.getDB(datablease);
//获取users DBCollection；如果默认没有创建，mongodb会自动创建
table = db.getCollection(tablelename);
//DO SOMETHING
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (MongoException e) {
e.printStackTrace();
}
}

public MongDbCRUD(String host, int port, String datablease, String tablelename){
try {
mongo = new Mongo(host, port);
// 连接池
MongoOptions opt = mongo.getMongoOptions();
opt.connectionsPerHost =  10  ; //poolsize
opt.threadsAllowedToBlockForConnectionMultiplier =  10 ;

//获取temp DB；如果默认没有创建，mongodb会自动创建
db = mongo.getDB(datablease);
//获取users DBCollection；如果默认没有创建，mongodb会自动创建
table = db.getCollection(tablelename);
//DO SOMETHING
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (MongoException e) {
e.printStackTrace();
}
}

public static void free(){
if(mongo!=null){
mongo.close();
}
mongo = null;
db = null;
table = null;
System.gc();
}

public static DBCollection getDBCollection(){
return table;
}

public void add(DBObject row){
table.save(row);
}

public void query(){
DBCursor cur = table.find();
while (cur.hasNext()) { 
DBObject dbobject = cur.next();
System.out.println(dbobject.get("key"));//get value
} 
}

}

3、mongo.properties内容

#mongodb setting
mongo.host=192.168.20.38
mongo.port=27017
mongo.database=map
mongo.table.bound=bound
mongo.username=username
mongo.pwd=pwd