java 调用 mongo （一）连接mongo，获取对象

 //1.创建链接
        //MongoClient client = new MongoClient();

        MongoCredential credential = MongoCredential.createCredential(
                "***", "license", "****".toCharArray());

        ServerAddress serverAddress = new ServerAddress("ip", post);
        MongoClient mongoClient = new MongoClient(serverAddress, Arrays.asList(credential));
        //  DB db = mongoClient.getDB("mydb");

        //2.打开数据库test
        MongoDatabase db = mongoClient.getDatabase("license");
        System.out.println("db----"+db);

        //3.获取集合
        MongoCollection<Document> collection = db.getCollection("license");

        System.out.println("collection----"+collection);
        //4.查询获取文档集合  FindIterable<Document> documents = collection.find().limit(5);
        FindIterable<Document> documents = collection.find();


        //System.out.println(documents.first()+"----");
        //5.循环遍历
        for (Document document : documents) {
            System.out.println("--document--"+document);
        }
        System.out.println("collection----"+collection.count());
        //6.关闭连接
        mongoClient.close();

<dependency>
            <groupId>org.mongodb</groupId>
            <artifactId>mongo-java-driver</artifactId>
            <version>3.0.4</version>
        </dependency>

引入库 目前来看只有 3.0.4 能用new 对象。其他版本都尝试过，

MongoClient 都是虚拟的。