SpringBoot操作MongoDB数据库

        spring-data-mongodb提供了MongoTemplate和MongoRepository两种方式访问MongoDB，MongoRepository的方式访问较为简单，MongoTemplate方式较为灵活，这两种方式在Java对于MongoDB的运用中相辅相成。

一、基于MongoTemplate开发

引入依赖

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

修改yml配置

spring:
  data:
    mongodb:
      #192.168.217.128根据自己的ip进行修改
      #test是MongoDB的集合名称 也就是表名
      uri: mongodb://192.168.217.128:27017/test

添加实体类

@Data
@AllArgsConstructor
@Document("User") //指定了这个模型类型所对应的集合名称即collection 表名
public class User {
    @Id //自动生成的主键ID 主键 不可重复 自带索引
    private String id;
    private String name;
    private Integer age;
}

方法测试

@SpringBootTest
public class MongoTemplateTest {
    @Autowired
    private MongoTemplate mongoTemplate;

    @Test
    public void testMongoDB(){
        //向表中插入数据
        User user = new User(null,"张三",20);
        User user1 = new User(null,"李四",16);
        mongoTemplate.insert(user);
        mongoTemplate.insert(user1);

        //查询表中所有记录
        List<User> userList = mongoTemplate.findAll(User.class);
        System.out.println(userList);
        //[User(id=63acf541e6af652ac74fd008,name=张三,age=20),// User(id=63acf541e6af652ac74fd009,name=李四,age=16)]

        //根据表中id查询记录
        User user2 = mongoTemplate.findById("63acf541e6af652ac74fd008",User.class);
        System.out.println(user2);//User(id=63acf541e6af652ac74fd008,age=20)

        //条件查询
        Query query = new Query(Criteria.where("name").is("李四").and("age").is(16));
        List<User> users = mongoTemplate.find(query,User.class);
        System.out.println(users);//[User(id=63acf541e6af652ac74fd009,age=16)]


        //根据_id删除表中记录
        Query query2 = new Query(Criteria.where("_id").is("63acf541e6af652ac74fd008"));
        DeleteResult remove = mongoTemplate.remove(query2,User.class);
        //获取删除记录的个数
        long count = remove.getDeletedCount();
        System.out.println(count);//1

        //删除表中所有数据
        Query query3 = new Query();
        mongoTemplate.remove(query3,User.class);
    }
}

二、基于MongoRepository开发

        Spring Data提供了对MongoDB数据访问的支持，我们只需要继承MongoRepository类，按照Spring Data规范就可以了。

构建仓库

public interface UserRepository extends MongoRepository<User,String> {
}

方法测试

@SpringBootTest
public class MongoRepositoryTest {
    @Autowired
    private UserRepository userRepository;

    @Test
    public void test(){
        //向数据库表中插入数据
        User user = new User(null,"张三三",18);
        User user1 = new User(null,16);
        userRepository.save(user);
        userRepository.save(user1);

        //查询数据库表中所有记录
        List<User> all = userRepository.findAll();
        System.out.println(all);
        //[User(id=63acf24938e0d1033d50dc20,name=张三三,age=18),// User(id=63acf24938e0d1033d50dc21,age=16)]

        //按照id查询表中数据
        User user2 = userRepository.findById("63acf24938e0d1033d50dc20").get();
        System.out.println(user2);//User(id=63acf24938e0d1033d50dc20,age=18)

        //按条件(姓名与年龄)查询
        Example<User> example = Example.of(new User(null,16));
        List<User> list = userRepository.findAll(example);
        System.out.println(list);//User(id=63acf24938e0d1033d50dc21,age=16)

        //模糊查询
        User user3 = new User(null,"三",18);
        //模糊查询匹配规则
        ExampleMatcher matcher = ExampleMatcher.matching()
                .withStringMatcher(ExampleMatcher.StringMatcher.CONTAINING)
                .withIgnoreCase(true);//忽略大小写
        Example<User> example1 = Example.of(user3,matcher);
        List<User> list1 = userRepository.findAll(example1);
        System.out.println(list1);//User(id=63acf24938e0d1033d50dc20,age=18)

        //分页查询
        Pageable pageable = PageRequest.of(0,2);//设置分页参数：第1页 每页2条数据
        Page<User> page = userRepository.findAll(pageable);
        System.out.println("Page的总页数是：" + page.getTotalPages() + ",Page的总记录条数是：" + page.getTotalElements());
        //Page的总页数是：1 +,Page的总记录条数是：2

        //根据_id修改信息
        User user4 = userRepository.findById("63acf24938e0d1033d50dc20").get();
        user4.setName("王五");//将取出的信息修改其name
        userRepository.save(user4);

        //根据id删除
        userRepository.deleteById("63acf24938e0d1033d50dc20");

        //删除全部
        userRepository.deleteAll();
    }
}