spring boot项目创建，集成mybatis配置mysql连接，编写测试代码完成访问接口查询数据库

springboot项目创建mybatis配置mysql，完成查询数据库测试 准备工作： 1.去https://start.spring.io/创建项目，本例使用的是 springboot 2.4.0-SNAPSHOT ，Maven，JAVA 8，依赖WEB MVC。 2.JAVA开发工具导入Maven项目，本例使用的是eclipse。 3.resources文件夹下创建mapper文件夹备用 4.本地要有jdk8环境便于测试 一.首先引入mysql和mybatis的jar包

<!--mysql数据库驱动--> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <!--mybatis--> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>2.1.0</version> </dependency>

二.再resources文件夹下创建application.yml和mybatis-config.xml配置文件 1.application.yml 配置端口，数据库配置，mybatis配置

server: port: 9898 spring: #数据库连接配置 datasource: driver-class-name: com.mysql.cj.jdbc.Driver url: jdbc:mysql://IP:3306/test?characterEncoding=utf-8&useSSL=false username: 账号 password: 密码 #mybatis的相关配置 mybatis: #mapper配置文件 mapper-locations: classpath:mapper/*.xml type-aliases-package: cn.richwit.blog.entity config-location: classpath:mybatis-config.xml

2.mybatis-config.xml(空文件什么不配置也要创建)

<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <!--以下已经在application.yml中配置过了--> <!--<typeAliases>--> <!--<package name="com.example.domain"/>--> <!--</typeAliases>--> <!--<mappers>--> <!--<mapper resource="mapper/UserMapper.xml"/>--> <!--</mappers>--> </configuration>

三.编写测试代码 1.entity实体类

package cn.richwit.blog.entity; import java.util.Date; /** * @version 1.0 */ public class Article { //id private int article_id; //标题 private String article_title; //内容 private String article_comtent; //类型 private String article_type; //用户id private int user_id; //阅读量 private long reading_quantity; private Date create_time; private Date update_time; public Article() { super(); } public Article(int article_id, String article_title, String article_comtent, String article_type, int user_id, long reading_quantity, Date create_time, Date update_time) { super(); this.article_id = article_id; this.article_title = article_title; this.article_comtent = article_comtent; this.article_type = article_type; this.user_id = user_id; this.reading_quantity = reading_quantity; this.create_time = create_time; this.update_time = update_time; } public int getArticle_id() { return article_id; } public void setArticle_id(int article_id) { this.article_id = article_id; } public String getArticle_title() { return article_title; } public void setArticle_title(String article_title) { this.article_title = article_title; } public String getArticle_comtent() { return article_comtent; } public void setArticle_comtent(String article_comtent) { this.article_comtent = article_comtent; } public String getArticle_type() { return article_type; } public void setArticle_type(String article_type) { this.article_type = article_type; } public int getUser_id() { return user_id; } public void setUser_id(int user_id) { this.user_id = user_id; } public long getReading_quantity() { return reading_quantity; } public void setReading_quantity(long reading_quantity) { this.reading_quantity = reading_quantity; } public Date getCreate_time() { return create_time; } public void setCreate_time(Date create_time) { this.create_time = create_time; } public Date getUpdate_time() { return update_time; } public void setUpdate_time(Date update_time) { this.update_time = update_time; } }

2.controller控制层

package cn.richwit.blog.controller; import java.util.HashMap; import java.util.Map; import org.apache.commons.lang.StringUtils; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import cn.richwit.blog.entity.Article; import cn.richwit.blog.service.ArticleService; /** * @version 1.0 */ @RestController @RequestMapping("/article") public class ArticleController { @Autowired private ArticleService articleService; @RequestMapping("/getarticlebyid") public Map<String,Object> getArticleById(String articleId){ Map<String,Object> map = new HashMap<>(); if(StringUtils.isBlank(articleId)) { map.put("err", "错误请求！"); return map; } Article article = articleService.getArticleById(Integer.parseInt(articleId)); if(article == null) { map.put("success", false); }else { map.put("success", true); map.put("article", article); } return map; } }

3.service服务层 接口

package cn.richwit.blog.service; import cn.richwit.blog.entity.Article; /** * @version 1.0 */ public interface ArticleService { Article getArticleById(int id); }

实现类

package cn.richwit.blog.service; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import cn.richwit.blog.dao.ArticleDao; import cn.richwit.blog.entity.Article; /** * @version 1.0 */ @Service public class ArticleServiceImpl implements ArticleService{ @Autowired private ArticleDao articleDao; @Override public Article getArticleById(int id) { Article article = articleDao.findArticleById(id); return article; } }

4.dao数据层

package cn.richwit.blog.service; import java.util.HashMap; import java.util.Map; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import cn.richwit.blog.dao.ArticleDao; import cn.richwit.blog.entity.Article; /** * @version 1.0 */ @Service public class ArticleServiceImpl implements ArticleService{ @Autowired private ArticleDao articleDao; @Override public Map<String, Object> getArticleById(int id) { Map<String, Object> map = new HashMap<>(); Article article = articleDao.findArticleById(id); map.put("article", article); return map; } }

5.dao接口对应的mapper

<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > <mapper namespace="cn.richwit.blog.dao.ArticleDao"> <select id="findArticleById" parameterType="int" resultType="Article"> SELECT * FROM Article where article_id = #{articleId} </select> </mapper>

6.最后再启动类上加上扫描dao接口

package cn.richwit.blog; import org.mybatis.spring.annotation.MapperScan; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication @MapperScan("cn.richwit.blog.dao") public class BlogApplication { public static void main(String[] args) { SpringApplication.run(BlogApplication.class, args); } }

7.创建实体类对应的数据库表，并插入一条测试数据 最后运行启动类 访问：http://127.0.0.1:9898/article/getarticlebyid?articleId=1