java连接Mongodb进行增删改查

1.创建maven项目

        <dependency>
            <groupId>org.mongodb</groupId>
            <artifactId>mongodb-driver</artifactId>
            <version>3.4.1</version>
        </dependency>

2.编写代码

 1.查询所有

package com.czxy.mongodb;

import com.alibaba.fastjson.JSON;
import com.mongodb.*;

import java.util.List;
import java.util.Set;

public class Find {
    public static void main(String[] args) {
        //客户端链接
        MongoClient mongodbClint = new MongoClient("localhost", 27017);
        // 获取所有的数据库
        List<String> databaseNames = mongodbClint.getDatabaseNames();
        for (String databaseName : databaseNames) {
            System.out.println("数据库名称  "+databaseName);
        }
        // 连接指定的数据库
        DB db = mongodbClint.getDB("text");

        //获取当前数据库下的所有集合名称
        Set<String> collectionNames = db.getCollectionNames();
        for (String dbname : collectionNames) {
            System.out.println("集合名称  "+dbname);
        }
        // 连接指定的集合
        DBCollection collection = db.getCollection("stus");
         // 数据集合信息
        DBCursor dbObjects = collection.find();

        while (dbObjects.hasNext()){
            //读取数据
            DBObject next = dbObjects.next();
            // json 格式转换
            Stus parse = JSON.parseObject(next.toString(), Stus.class);
            // 数据输出
            System.out.println(parse);
        }
    }
}

2.添加数据

package com.czxy.mongodb;

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

import java.util.HashMap;
import java.util.Map;

public class Insert {
    public static void main(String[] args) {
        // 获取连接
        MongoClient mongodbClint = new MongoClient("localhost", 27017);
        // 连接数据库
        MongoDatabase database = mongodbClint.getDatabase("text");
        // 获取对象
        MongoCollection<Document> stus = database.getCollection("stus");
        Map<String, Object> map=new HashMap();
        map.put("name", "诸葛亮");
        map.put("sex", "男");
        map.put("age", 35.0);
        map.put("address", "南阳");
        Document document = new Document(map);
        System.out.println(document);
        stus.insertOne(document);
    }
}

3.删除

package com.czxy.mongodb;

import com.mongodb.BasicDBObject;
import com.mongodb.MongoClient;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;

/**
 *  删除
 */
public class Delete {
    public static void main(String[] args) {
        //获取连接
        MongoClient location = new MongoClient("localhost", 27017);
        // 连接数据库
        MongoDatabase database = location.getDatabase("text");
        //获取集合封账对象
        MongoCollection<Document> collection = database.getCollection("stus");
        // 删除的条件
        BasicDBObject dbObject = new BasicDBObject("name", "诸葛亮");
        // 删除符合条件的第一个
          collection.deleteOne(dbObject);
          // 删除符合条件的所有
//          collection.deleteMany(new BasicDBObject("name","lisi"));
    }
}

4.修改

package com.czxy.mongodb;

import com.mongodb.BasicDBObject;
import com.mongodb.MongoClient;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;

import java.awt.*;

public class Update {
    public static void main(String[] args) {
        // 获取连接
        MongoClient mongoClient = new MongoClient();
        // 连接数据库
        MongoDatabase database = mongoClient.getDatabase("text");
        // 得到集合封装队象
        MongoCollection<Document> stuo = database.getCollection("stus");
        // 查询条件
         BasicDBObject upFind = new BasicDBObject("name", "wangwu");
        // 修改的值
        BasicDBObject upNew = new BasicDBObject("$set", new BasicDBObject("address", "高老庄"));
        // 修改符合条件的第一个值
        stuo.updateOne(upFind, upNew);
        //修改符合条件的全部
//        stuo.updateMany(upFind, upNew);
    }
}

5.条件查询

package com.czxy.mongodb;

import com.alibaba.fastjson.JSON;
import com.mongodb.BasicDBObject;
import com.mongodb.MongoClient;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;

public class FindEq {
    public static void main(String[] args) {
        // 获取连接
        MongoClient mongoClient = new MongoClient();
        // 连接数据库
        MongoDatabase database = mongoClient.getDatabase("text");
        // 得到集合封装队象
        MongoCollection<Document> stus = database.getCollection("stus");
        // 查询条件
        BasicDBObject find = new BasicDBObject("name", "wangwu");
        // 得到查询结果
        FindIterable<Document> results = stus.find(find);
        // 集合遍历
        for (Document result : results) {
            // 格式转换
            String s = JSON.toJSONString(result);
            // 查询结果输出
            System.out.println(JSON.parseObject(s,Stus.class));
        }
    }
}