本节使用SpringBoot 2.1.9.RELEASE,示例源码在:https://github.com/laolunsi/spring-boot-examples


SpringBoot可以非常方便地引入和操作MongoDB。本节分两部分,记录个人学习SpringBoot使用MongoDB数据库的一些知识。

第一部分是一个简单的springboot连接mongo的demo,测试查询功能。

第二部分是基于mongo实现的增删改查数据示例。


一、A simple demo

首先来演示SpringBoot项目引入MongoDB,以及一个简单的findAll操作。

maven依赖:

<dependency>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency>

环境配置:

application.yml文件中写入如下配置,test表示MongoDB中的test表

spring:
  data:
    mongodb:
      uri: "mongodb://localhost:27017/test"

以一个bean类为例:

package com.example;

public class User {

    private String id;
    private String name;
    private Integer age;
    private Integer grade;

    // ... ignore getter and setter
    
    
    // override its toString method
    @Override
    public String toString() {
        return "User{" +
                "id='" + id + '\'' +
                ", name='" + name + '\'' +
                ", age=" + age +
                ", grade=" + grade +
                '}';
    }
}

在MongoDB数据库中新建一个collection(也就是表),名字叫user,插入几条数据,比如:

file
注:这里用的可视化工具是robo 3t:https://robomongo.org/

我们这里先默认JavaBean的字段与user表的字段名保持一致。

下面我们编写测试类:

@SpringBootTest
@RunWith(SpringRunner.class)
public class MongoTest {

    @Autowired
    private MongoTemplate mongoTemplate;

    @Test
    public void test1() {
        List<User> userList = mongoTemplate.findAll(User.class);
        if (userList != null && userList.size() > 0) {
            userList.forEach(user -> {
                System.out.println(user.toString());
            });
        }
    }

}

运行测试类,输出如下:

User{id='5d243534514701183f5fcab8', name='zf0', age=12, grade=1}
User{id='5d243534514701183f5fcab9', name='zf1', age=13, grade=2}
User{id='5d243534514701183f5fcaba', name='zf2', age=14, grade=3}
User{id='5d243534514701183f5fcabb', name='zf3', age=15, grade=4}
User{id='5d243534514701183f5fcabc', name='zf4', age=16, grade=5}

二、基于SpringBoot的MongoDB增删改查操作

下面来实现一个基于SpringBoot的对MongoDB增删改查操作的简单示例,依然使用上面的环境:

maven:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <scope>test</scope>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency>

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.60</version>
</dependency>

yml:

server:
  port: 8866

spring:
  data:
    mongodb:
      uri: "mongodb://localhost:27017/test"

User类:

这里我们清楚一下之前的数据,把mongo里的user表里的数据全部删掉。

file

注:这里用的可视化工具admin-mongo:

新建一个不同的user类:

@Document("user")
public class User {

    @Id
    private String id;

    @Field("name")
    private String name;

    @Field("password")
    private String password;

    @Field("address")
    private String address;

    @Field("create_time")
    private Date createTime;

    @Field("last_update_time")
    private Date lastUpdateTime;

    // ... ignore getter and setter methods

    @Override
    public String toString() {
        return JSONObject.toJSONString(this);
    }
}

此处定义一个JsonResult类,用于封装接口返回数据:

import com.alibaba.fastjson.JSONObject;

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

public class JsonResult {

    /**
     * 未登录
     */
    public static final int NO_LOGIN = 400;

    /**
     * 登录失败
     */
    public static final int LOGIN_FAILED = 401;

    /**
     * TOKEN过期
     */
    public static final int TOKEN_EXPIRED = 402;

    /**
     * 无权限
     */
    public static final int NO_PERMISSION = 403;


    private Boolean success;
    private Integer code;
    private String msg;
    private Object data;

    public JsonResult(Boolean success) {
        this.success = success;
    }

    public JsonResult(Boolean success, String msg) {
        this.success = success;
        this.msg = msg;
    }

    public JsonResult(Integer code, Boolean success, String msg) {
        this.code = code;
        this.success = success;
        this.msg = msg;
    }

    public JsonResult(Boolean success, Object data) {
        this.success = success;
        this.data = data;
    }

    public JsonResult(Boolean success, Integer code, String msg, Object data) {
        this.success = success;
        this.code = code;
        this.msg = msg;
        this.data = data;
    }

    // ... ignore getter and setter methods

    public void put(String key, Object value) {
        if (data == null) {
            data = new HashMap<>();
        }
        ((Map) data).put(key, value);
    }

    public void putAll(Map<String, Object> map) {
        if (data == null) {
            data = new HashMap<>();
        }
        ((Map) data).putAll(map);
    }

    @Override
    public String toString() {
        return JSONObject.toJSONString(this);
    }
}

下面编写测试接口类,实现用户的新增、删除、更新、查询功能

UserController类:

@RestController
@RequestMapping(value = "user")
public class UserController {

    @Autowired
    private MongoTemplate mongoTemplate;

    @GetMapping(value = "")
    public JsonResult list() {
        List<User> userList = mongoTemplate.findAll(User.class, "user");
        return new JsonResult(true, userList);
    }

    @PostMapping(value = "")
    public JsonResult add(User user) {
        String msg = verifySaveForm(user);
        if (!StringUtils.isEmpty(msg)) {
            return new JsonResult(false, msg);
        }

        if (user.getId() == null) {
            user.setCreateTime(new Date());
            user.setLastUpdateTime(new Date());
            User newUser = mongoTemplate.insert(user, "user");
            return new JsonResult(true, newUser);
        } else {
            Query query = new Query();
            query.addCriteria(Criteria.where("_id").is(user.getId()));

            Update update = new Update();
            update.set("name", user.getName());
            update.set("password", user.getPassword());
            update.set("address", user.getAddress());
            update.set("last_update_time", new Date());

            UpdateResult updateResult = mongoTemplate.updateFirst(query, update, "user");
            return new JsonResult(true, updateResult);
        }
    }

    @DeleteMapping(value = "{id}")
    public JsonResult delete(@PathVariable String id) {
        Query query = new Query();
        query.addCriteria(Criteria.where("_id").is(id));
        DeleteResult deleteResult = mongoTemplate.remove(query, User.class, "user");
        return new JsonResult(true, deleteResult);
    }

    // private methods

    private String verifySaveForm(User user) {
        if (user == null || StringUtils.isEmpty(user.getName())) {
            return "用户名不能为空";
        } else if (user.getPassword() == null) {
            return "密码不能为空";
        }

        return null;
    }
}

下面用postman模拟一下请求:

新增用户

file

查看Mongodb:

file

更改数据,新增多个用户:

file

列表查询

file

更改user

file

file

删除user:
file

file


好,到此为止,我们已经在SpringBoot项目中引入了MongoDB,并实现了基本的增删改查操作,这将是我们使用MongoDB开发更加复杂的业务的基础!

Last modification:November 16th, 2019 at 12:15 am
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