Spring Boot中MongoDB的使用和实战

小鱼儿 2023-09-30 16:15 15阅读 0赞

> **创作不易 觉得有帮助请点赞关注收藏~~~**

**MongoDB是一个基于分布式文件存储的NoSQL数据库，由C++语言编写，旨在为Web应用提供可扩展的高性能数据存储解决方案。**

**MongoDB是一个介于关系数据库和非关系数据库之间的产品，是非关系数据库中功能最丰富最像关系数据库的，它支持的数据结构非常松散，是类似JSON的BSON格式，因此可以存储比较复杂的数据类型。Mongo最大的特点是它支持的查询语言非常强大，其语法有点类似与 面向对象的查询语言，几乎可以实现类似关系数据库单表查询的绝大部分功能，而且还支持对数据建立索引。**

## 一：安装MongoDB ##

> 官方网站https://www.mongodb.com/downlad-center/community下载

## 二：Spring Boot整合MongoDB ##

Spring对MongoDB的支持主要是通过Spring Data MongoDB实现的，Spring Data MongoDB提供了如下功能

1：对象/文档映射注解

2：MongoTemplate

提供了数据访问的方法

3：Repository

public interface PersonRepository extends MongoRepository<Person,String>{
    }

## 实战进行增删改查 ##

### 1：创建基于spring-boot-starter-data-mongodb依赖的Spring Boot应用 ###

### 2：配置application.properties文件 ###

server.servlet.context-path=/ch6_8
    #让控制器输出的JSON字符串格式更美观
    spring.jackson.serialization.indent-output=true

### 3：创建领域模型 ###

创建名为com.ch.ch6\_8.domain的包 并在该包中创建领域模型Person以及人去过的Loation

Person代码如下

package com.ch.ch6_8.domain;
    import java.util.ArrayList;
    import java.util.List;
    import org.springframework.data.annotation.Id;
    import org.springframework.data.mongodb.core.mapping.Document;
    import org.springframework.data.mongodb.core.mapping.Field;
    @Document
    public class Person {
    	@Id
    	private String pid;
    	private String pname;
    	private Integer page;
    	private String psex;
    	@Field("plocs")
    	private List<Location> locations = new ArrayList<Location>();
    	public Person() {
    		super();
    	}
    	public Person(String pname, Integer page, String psex) {
    		super();
    		this.pname = pname;
    		this.page = page;
    		this.psex = psex;
    	}
    	public String getPid() {
    		return pid;
    	}
    	public void setPid(String pid) {
    		this.pid = pid;
    	}
    	public String getPname() {
    		return pname;
    	}
    	public void setPname(String pname) {
    		this.pname = pname;
    	}
    	public Integer getPage() {
    		return page;
    	}
    	public void setPage(Integer page) {
    		this.page = page;
    	}
    	public String getPsex() {
    		return psex;
    	}
    	public void setPsex(String psex) {
    		this.psex = psex;
    	}
    	public List<Location> getLocations() {
    		return locations;
    	}
    	public void setLocations(List<Location> locations) {
    		this.locations = locations;
    	}
    }

Location代码如下

package com.ch.ch6_8.domain;
    public class Location {
    	private String locName;
    	private String year;
    	public Location() {
    		super();
    	}
    	public Location(String locName, String year) {
    		super();
    		this.locName = locName;
    		this.year = year;
    	}
    	public String getLocName() {
    		return locName;
    	}
    	public void setLocName(String locName) {
    		this.locName = locName;
    	}
    	public String getYear() {
    		return year;
    	}
    	public void setYear(String year) {
    		this.year = year;
    	}
    }

### 4：创建数据访问接口 ###

package com.ch.ch6_8.repository;
    import java.util.List;
    import org.springframework.data.mongodb.repository.MongoRepository;
    import org.springframework.data.mongodb.repository.Query;
    import com.ch.ch6_8.domain.Person;
    public interface PersonRepository extends MongoRepository<Person, String>{
    	Person findByPname(String pname);//支持方法名查询，方法名命名规范参照表6.1
    	@Query("{'psex':?0}")//JSON字符串
    	List<Person> selectPersonsByPsex(String psex);
    }

### 5：创建控制器层 ###

创建控制器类TestMongoDBController

package com.ch.ch6_8.controller;
    import java.util.ArrayList;
    import java.util.List;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    import com.ch.ch6_8.domain.Location;
    import com.ch.ch6_8.domain.Person;
    import com.ch.ch6_8.repository.PersonRepository;
    @RestController
    public class TestMongoDBController {
    	@Autowired
    	private PersonRepository personRepository;
    	@RequestMapping("/save")
    	public List<Person> save() {
    		List<Location> locations1 = new ArrayList<Location>();
    		Location loc1 = new Location("北京","2019");
    		Location loc2 = new Location("上海","2018");
    		locations1.add(loc1);
    		locations1.add(loc2);
    		
    		List<Location> locations2 = new ArrayList<Location>();
    		Location loc3 = new Location("广州","2017");
    		Location loc4 = new Location("深圳","2016");
    		locations2.add(loc3);
    		locations2.add(loc4);
    		
    		List<Person> persons = new ArrayList<Person>();
    		Person p1 = new Person("陈恒1", 88, "男");
    		p1.setLocations(locations1);
    		Person p2 = new Person("陈恒2", 99, "女");
    		p2.setLocations(locations2);
    		persons.add(p1);
    		persons.add(p2);
    		
    		return personRepository.saveAll(persons);
    	}
    	@RequestMapping("/findByPname")
    	public Person findByPname(String pname) {
    		return personRepository.findByPname(pname);
    	}
    	@RequestMapping("/selectPersonsByPsex")
    	public List<Person> selectPersonsByPsex(String psex) {
    		return personRepository.selectPersonsByPsex(psex);
    	}
    	@RequestMapping("/updatePerson")
    	public Person updatePerson(String oldPname, String newPname) {
    		Person p1 = personRepository.findByPname(oldPname);
    		if(p1 != null)
    			p1.setPname(newPname);
    		return personRepository.save(p1);
    	}
    	@RequestMapping("/deletePerson")
    	public void updatePerson(String pname) {
    		Person p1 = personRepository.findByPname(pname);
    		personRepository.delete(p1);
    	}
    }

**运行主类后 可以使用MongoDB的图形界面管理工具MongoDB Compass打开查看已保存的数据**