1、File--->New--->Maven Project
2.
3.把下面代码放进pom.xml中
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.0.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
</dependency>
<dependency>
<groupId>org.apache.tomcat.embed</groupId>
<artifactId>tomcat-embed-jasper</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.1.1</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.21</version>
</dependency>
</dependencies>
4.新建controller、service、serviceImpl、mapper几个包如下图
controller代码:
package com.ansheng.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import com.ansheng.service.TestService;
@RestController
public class TestController {
@Autowired
private TestService testService;
@RequestMapping("/test")
public int test() {
int count=testService.queryCount();
return count;
}
}
service代码
package com.ansheng.service;
public interface TestService {
int queryCount();
}
serviceImpl代码
package com.ansheng.service.impl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.ansheng.mapper.TestMapper;
import com.ansheng.service.TestService;
@Service
public class TestServiceImpl implements TestService{
@Autowired
private TestMapper testMapper;
@Override
public int queryCount() {
// TODO Auto-generated method stub
return testMapper.queryCount();
}
}
mapper代码
package com.ansheng.mapper;
import org.apache.ibatis.annotations.Mapper;
@Mapper
public interface TestMapper {
int queryCount();
}
5.在src/main/resources 下面新建一个mapper文件夹,新建一个xml文件,名字和mapper(dao)接口一致,如下图
代码如下:
<?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.ansheng.mapper.TestMapper">
<select id="queryCount" resultType="java.lang.Integer">
select count(0) from fdy
</select>
</mapper>
6.在src/main/resources 下面新建一个配置文件,名字为:application.properties
如下图:
在配置文件中配置数据库信息和mapper.xml扫描信息,代码如下:
spring.datasource.url=jdbc:mysql://localhost:3306/biye
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
mybatis.mapperLocations=classpath:mapper/*.xml
代码截图:
7.下面是启动类,启动类扫描同一包下面或者子包中的类,所以在src/main/java/com/ansheng 下面新建启动类App
代码:
package com.ansheng;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class App {
public static void main(String[] args) {
SpringApplication.run(App.class, args);
}
}
然后运行就行了,亲测无误!