每日总结

用MongoDB的Java客户端编程

 

添加数据：English:45 Math:89  Computer:100

与上述数据对应的文档形式如下：

{

“name”: “scofield”,

“score”: {

“English”: 45,

“Math”: 89,

“Computer”: 100

}

}

  package mongo;

import java.util.ArrayList;

import java.util.List;

import org.bson.Document;

import com.mongodb.MongoClient;

import com.mongodb.client.MongoCollection;

import com.mongodb.client.MongoDatabase;

public class monggo {

  public static void main(String[] args) {

      MongoClient mongoClient = new MongoClient("localhost", 27017);

      MongoDatabase mongoDatabase = mongoClient.getDatabase("mongo_S");

     MongoCollection<Document> collection = mongoDatabase

              .getCollection("student");

      Document document = new Document("name", "scofield").append(

              "score",

              new Document("English", 45).append("Math", 89).append(

                      "Computer", 100));

      List<Document> documents = new ArrayList<Document>();

      documents.add(document);

      collection.insertMany(documents);

      System.out.println("文档插入成功");

  }

}

 获取scofield的所有成绩成绩信息(只显示score列)

 

package mongo;

 

import org.bson.Document;

 

import com.mongodb.MongoClient;

 

import com.mongodb.client.MongoCollection;

 

import com.mongodb.client.MongoCursor;

 

import com.mongodb.client.MongoDatabase;

 

import com.mongodb.client.model.Filters;

 

import static com.mongodb.client.model.Filters.eq;

 

public class monggo2{

 

    public static void main(String[] args) {

 

        MongoClient  mongoClient=new MongoClient("localhost",27017);

 

        MongoDatabase mongoDatabase = mongoClient.getDatabase("mongo_S");

 

        MongoCollection<Document> collection = mongoDatabase.getCollection("student");

 

        MongoCursor<Document>  cursor=collection.find( new Document("name","scofield")).

 

                projection(new Document("score",1).append("_id", 0)).iterator();

 

        while(cursor.hasNext())

 

            System.out.println(cursor.next().toJson());

 

    }

 

}