Java MongoDB 实例HelloWorld
一个简单的入门例子，演示连接客户端，怎样创建一个数据库、表，怎样实现数据的增、删、改、查等操作

1. 在Eclipse中建立一个Maven工程


2. 获取Mongo Java Driver

<dependency>  <groupId>org.mongodb</groupId>  <artifactId>mongo-java-driver</artifactId>  <version>2.11.0</version>  </dependency>

如果不使用Maven工程，可以从https://github.com/mongodb/mongo-java-driver/downloads获取jar包

3. HelloWorld

import java.net.UnknownHostException;import java.util.Date;import java.util.List;import java.util.Set;import com.mongodb.BasicDBObject;import com.mongodb.DB;import com.mongodb.DBCollection;import com.mongodb.DBCursor;import com.mongodb.MongoClient;import com.mongodb.MongoException;public class MongoDBExample {public static void main(String[] args) {try {// 1. 连接到MongoDB服务器MongoClient mongo = new MongoClient("localhost", 27017);// 2. 获取数据库// 如果指定的数据库[yourdb]不存在，MongoDB将会新建一个数据库DB db = mongo.getDB("yourdb");//显示所有数据库List<String> dbs = mongo.getDatabaseNames();for(String database: dbs){System.out.println("db: "+database);}// 3. 获取一个表// 如果表不存在，MongoDB将会新建一个DBCollection table = db.getCollection("users");//显示选择的数据库中所有表Set<String> tables = db.getCollectionNames();for(String coll : tables){System.out.println("table:　"+coll);}// 新增一条记录BasicDBObject document = new BasicDBObject();document.put("username", "yourname");document.put("password", "123456");document.put("age", 22);document.put("createdDate", new Date());table.insert(document);// 查找并显示一条记录BasicDBObject searchQuery = new BasicDBObject();searchQuery.put("username", "yourname");DBCursor cursor = table.find(searchQuery);while (cursor.hasNext()) {System.out.println(cursor.next());}//更新一条记录BasicDBObject query = new BasicDBObject();query.put("username", "yourname");BasicDBObject newDocument = new BasicDBObject();newDocument.put("username", "yourname-update");BasicDBObject updateObj = new BasicDBObject();updateObj.put("$set", newDocument);table.update(query, updateObj);//查找更新后的记录BasicDBObject searchQuery2 = new BasicDBObject().append("username", "yourname-update");DBCursor cursor2 = table.find(searchQuery2);while (cursor2.hasNext()) {System.out.println(cursor2.next());}System.out.println("End");} catch (UnknownHostException e) {e.printStackTrace();} catch (MongoException e) {e.printStackTrace();}}}

4. 运行结果


5. mongo 客户端


6. MongoDB客户端工具RockMongo界面