springboot作为一个微服务框架,给我们开发人员提供极大的便利,秉着约定大于配置的原则,通过starter包的形式为我们做了许多默认的配置,在进行数据持久化到关系型数据库时,我们一般都会首选spring data jpa,springboot为我们提供了starter包,只需配置很少的参数,就能满足我们的需求,非常方便。但是当我们遇到一些比较复杂的查询、多表关联查询及动态sql时,mybatis则在这方面更出色,并且在使用mybatis时我们可以通过sql优化来提高查询效率,springboot并没有给我们提供整合mybatis的starter包,因此我们需要自己整合。记录一下我的整合过程,以供后续参考。
本人使用的是sts,新建springboot项目加入web、mysql、mybatis模块,springboot版本2.0.1。
1、pom.xml
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.example</groupId> <artifactId>springboot-mybatis</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>springboot-mybatis</name> <description>Demo project for Spring Boot</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.0.BUILD-SNAPSHOT</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.3.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <!-- 分页插件 --> <dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper-spring-boot-starter</artifactId> <version>1.2.5</version> </dependency> <!-- alibaba的druid数据库连接池 --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid-spring-boot-starter</artifactId> <version>1.1.9</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <repositories> <repository> <id>spring-snapshots</id> <name>Spring Snapshots</name> <url>https://repo.spring.io/snapshot</url> <snapshots> <enabled>true</enabled> </snapshots> </repository> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories> <pluginRepositories> <pluginRepository> <id>spring-snapshots</id> <name>Spring Snapshots</name> <url>https://repo.spring.io/snapshot</url> <snapshots> <enabled>true</enabled> </snapshots> </pluginRepository> <pluginRepository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </pluginRepository> </pluginRepositories> </project>
2、实体类UserDomain.java
package com.example.demo.model; public class UserDomain { private Integer userId; private String userName; private String password; private String phone; //get和set方法 }
3、持久化接口
package com.example.demo.dao; import java.util.List; import com.example.demo.model.UserDomain; public interface UserDao { int insert(UserDomain record); List<UserDomain> selectUsers(); }
4、建表语句,注意数据库的ip和名称
CREATE TABLE t_user( user_id INT NOT NULL PRIMARY KEY AUTO_INCREMENT, user_name VARCHAR(255) NOT NULL , password VARCHAR(255) NOT NULL , phone VARCHAR(255) NOT NULL ) ENGINE=INNODB AUTO_INCREMENT=1000 DEFAULT CHARSET=utf8;
5、service层
package com.example.demo.service; import com.example.demo.model.UserDomain; import com.github.pagehelper.PageInfo; public interface UserService { int addUser(UserDomain user); PageInfo<UserDomain> findAllUser(int pageNum, int pageSize); } package com.example.demo.service.impl; import java.util.List; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import com.example.demo.dao.UserDao; import com.example.demo.model.UserDomain; import com.example.demo.service.UserService; import com.github.pagehelper.PageHelper; import com.github.pagehelper.PageInfo; @Service(value = "userService") public class UserServiceImpl implements UserService { @Autowired private UserDao userDao; @Override public int addUser(UserDomain user) { return userDao.insert(user); } //分页查询 @Override public PageInfo<UserDomain> findAllUser(int pageNum, int pageSize) { PageHelper.startPage(pageNum, pageSize); List<UserDomain> userDomains = userDao.selectUsers(); PageInfo result = new PageInfo(userDomains); return result; } }
6、控制层
package com.example.demo.controller; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.PostMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.ResponseBody; import com.example.demo.model.UserDomain; import com.example.demo.service.UserService; @Controller @RequestMapping(value = "/user") public class UserController { @Autowired private UserService userService; @ResponseBody @PostMapping("/add") public int addUser(UserDomain user){ return userService.addUser(user); } @ResponseBody @GetMapping("/all") public Object findAllUser( @RequestParam(name = "pageNum", required = false, defaultValue = "1") int pageNum, @RequestParam(name = "pageSize", required = false, defaultValue = "10") int pageSize){ return userService.findAllUser(pageNum,pageSize); } }
7、application.yml
server: port: 8080 spring: datasource: name: mysql_test type: com.alibaba.druid.pool.DruidDataSource #druid相关配置 druid: #监控统计拦截的filters filters: stat driver-class-name: com.mysql.jdbc.Driver #基本属性 url: jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=UTF-8&allowMultiQueries=true username: root password: root #配置初始化大小/最小/最大 initial-size: 1 min-idle: 1 max-active: 20 #获取连接等待超时时间 max-wait: 60000 #间隔多久进行一次检测,检测需要关闭的空闲连接 time-between-eviction-runs-millis: 60000 #一个连接在池中最小生存的时间 min-evictable-idle-time-millis: 300000 validation-query: SELECT ‘x‘ test-while-idle: true test-on-borrow: false test-on-return: false #打开PSCache,并指定每个连接上PSCache的大小。oracle设为true,mysql设为false。分库分表较多推荐设置为false pool-prepared-statements: false max-pool-prepared-statement-per-connection-size: 20 mybatis: mapper-locations: classpath:mapper/*.xml type-aliases-package: com.example.demo.model #pagehelper pagehelper: helperDialect: mysql reasonable: true supportMethodsArguments: true params: count=countSql returnPageInfo: check
8、UserMapper.xml
<?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="com.example.demo.dao.UserDao" > <sql id="BASE_TABLE"> t_user </sql> <sql id="BASE_COLUMN"> userId,userName,password,phone </sql> <insert id="insert" parameterType="com.example.demo.model.UserDomain"> INSERT INTO <include refid="BASE_TABLE"/> <trim prefix="(" suffix=")" suffixOverrides=","> userName,password, <if test="phone != null"> phone, </if> </trim> <trim prefix="VALUES(" suffix=")" suffixOverrides=","> #{userName, jdbcType=VARCHAR},#{password, jdbcType=VARCHAR}, <if test="phone != null"> #{phone, jdbcType=VARCHAR}, </if> </trim> </insert> <select id="selectUsers" resultType="com.example.demo.model.UserDomain"> SELECT <include refid="BASE_COLUMN"/> FROM <include refid="BASE_TABLE"/> </select> </mapper>
9、项目目录结构如下
在项目启动类SpringbootMybatisApplication上加上@MapperScan("com.example.demo.dao")注解,以便spring容器可以扫描到持久化接口,创建对应的代理类。启动项目,访问localhost:8080/user/add,添加用户;访问localhost:8080/user/all,可以看到分页查询效果。
补充:相比与映射文件方式,注解方式会更加方便,但是功能有限,使用注解方式只需做如下修改即可
1、持久化接口修改为如下
package com.example.demo.dao; import java.util.List; import org.apache.ibatis.annotations.Insert; import org.apache.ibatis.annotations.Mapper; import org.apache.ibatis.annotations.Param; import org.apache.ibatis.annotations.Select; import com.example.demo.model.UserDomain; @Mapper public interface UserDao { @Insert("INSERT INTO t_user(name, password, phone) VALUES(#{name}, #{password}, #{phone})") int insert(@Param("name") String name, @Param("password") String password, @Param("phone") String phone); @Select("SELECT * FROM t_user ") List<UserDomain> selectUsers(); }
2、删除掉UserMappper.xml文件,同时启动类上的@MapperScan可以去掉。
原文地址:https://www.cnblogs.com/hhhshct/p/9245050.html