Mongo Java驱动程序迭代器身份验证问题

import com.mongodb.MongoClient;
import com.mongodb.MongoClientOptions;
import com.mongodb.MongoCredential;
import com.mongodb.MongoException;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;

public class MongoDBExample {
    public static void main(String[] args) {
        // 设置MongoDB连接信息
        String host = "mongodb://localhost:27017";
        String database = "mydb";
        String username = "myuser";
        String password = "mypassword";

        try {
            // 创建MongoCredential对象
            MongoCredential credential = MongoCredential.createCredential(username, database, password.toCharArray());

            // 创建MongoClientOptions对象
            MongoClientOptions options = MongoClientOptions.builder().build();

            // 创建MongoClient对象
            MongoClient client = new MongoClient(new ServerAddress(host), credential, options);

            // 创建MongoDatabase对象
            MongoDatabase db = client.getDatabase(database);

            // 进行身份验证
            db.authenticate(username, password.toCharArray());

            // 创建MongoCollection对象
            MongoCollection<Document> collection = db.getCollection("mycollection");

            // 创建迭代器并进行数据查询
            MongoCursor<Document> cursor = collection.find().iterator();
            while (cursor.hasNext()) {
                Document document = cursor.next();
                System.out.println(document.toJson());
            }

            // 关闭连接
            client.close();
        } catch (MongoException e) {
            e.printStackTrace();
        }
    }
}