mongoDB是一个使用非常广的非关系型数据库，在springboot中，可以非常方便的实现CRUD操作。

1.pom配置

目前大多数项目都用maven进行依赖包管理，因此，本文也采用maven进行配置。pom需要增加如下依赖：

       <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <!-- MongoDB -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-mongodb</artifactId>
        </dependency>
        <!-- junit test -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!-- lombok -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.10</version>
            <scope>provided</scope>
        </dependency>

主要的依赖包有三个：
spring-boot-starter 核心启动包，spring-boot-starter-data-mongodb mongoDB的相关依赖包，spring-boot-starter-test junit单元测试包。
其他的包如 lombok 则是为了省略部分代码。

2.数据模型类

package com.dhb.domain;

import org.springframework.data.annotation.Id;
import org.springframework.data.mongodb.core.mapping.Document;

import lombok.Data;

@Document(collection = "users")
@Data
public class User {

    @Id
    private String id;
    
    private String name;
    
    private int age;

    public User(String name,int age){
        this.name = name;
        this.age = age;
    }
    
}

通过lombok的@Data注解，省略了get和set方法。
@Document 表示映射到mongoDB中的表。collection = "users" 通过collection进行指定。
@Id 映射mongoDB中的ID字段。

3.cuid方法Repository

springBoot提供了一个MongoRepository接口，只需要继承该接口即可。亦可自定义方法。

package com.dhb.domain;

import org.springframework.data.mongodb.repository.MongoRepository;

public interface UserMongoRepository extends MongoRepository<User, Integer> {

    User findByName(String name);

}

4.junit单元测试

测试代码如下：

package com.dhb.test;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.dhb.domain.User;
import com.dhb.domain.UserMongoRepository;

@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest
public class UserMongoRepositoryTest {

    @Autowired
    private UserMongoRepository userMongoRepository;

    @Before
    public void setUp() throws Exception {
        User user1 = new User("user1", 19);
        User user2 = new User("user2", 20);
        // save product, verify has ID value after save
        assertNull(user1.getId());
        assertNull(user2.getId());// null before save
        this.userMongoRepository.save(user1);
        this.userMongoRepository.save(user2);
        assertNotNull(user1.getId());
        assertNotNull(user2.getId());
    }

    @Test
    public void testFetchData() {
        /* Test data retrieval */
        User userA = userMongoRepository.findByName("user1");
        assertNotNull(userA);
        assertEquals(19, userA.getAge());
        /* Get all products, list should only have two */
        Iterable<User> users = userMongoRepository.findAll();
        int count = 0;
        for (User p : users) {
            count++;
        }
        assertEquals(count, 2);
    }

    @Test
    public void testDataUpdate() {
        /* Test update */
        User userB = userMongoRepository.findByName("user2");
        userB.setAge(40);
        userMongoRepository.save(userB);
        User userC = userMongoRepository.findByName("user2");
        assertNotNull(userC);
        assertEquals(40, userC.getAge());
    }

    @After
    public void tearDown() throws Exception {
        this.userMongoRepository.deleteAll();
    }

}

执行结果：

执行结果