springboot整合mybatis

1.导入依赖

2.配置druid连接池

DruidConfig.java

package com.law.mybatis_demo.config;

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import javax.sql.DataSource;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
@Configuration
public class DruidConfig {
    @ConfigurationProperties("spring.datasource")
    @Bean
    public DataSource druid(){
        return new DruidDataSource();
    }
    //配置druid的监控
    //1、配置一个管理后台的servlet
    @Bean
    public ServletRegistrationBean statViewServlet(){
        ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(),"druid/*");
        Map<String,String> initParames = new HashMap<>();
        initParames.put("loginUsername","admin");
        initParames.put("loginPassword","123456");
        initParames.put("allow","localhost");
        bean.setInitParameters(initParames);
        return bean;
    }
    //2、配置一个web监控的filter
    @Bean
    public FilterRegistrationBean webStatFilter(){
        FilterRegistrationBean bean = new FilterRegistrationBean();
        bean.setFilter(new WebStatFilter());
        Map<String,String> initParams = new HashMap<>();
        initParams.put("exclusion","*.js,*.css,/druid/*");
        bean.setInitParameters(initParams);
        bean.setUrlPatterns(Arrays.asList("/*"));
        return bean;
    }
}

spring:
  datasource:
#   数据源基本配置
    username: root
    password: root
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/spring_mybatis
    type: com.alibaba.druid.pool.DruidDataSource
#   数据源其他配置
    initialSize: 5
    minIdle: 5
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true
  #   配置监控统计拦截的filters，去掉后监控界面sql无法统计，'wall'用于防火墙
    filters: stat,wall,log4j
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true　　　　                             

3、使用mybatis注解版

写mapper接口

package com.law.mybatis_demo.mapper;

import com.law.mybatis_demo.bean.Department;
import org.apache.ibatis.annotations.*;

//指定这是一个操作数据库的mapper
@Mapper
public interface DepartmentMapper {
    @Select("select * from department where id=#{id}")
    public Department getDeptById(Integer id);

    @Delete("delete * from department where id=#{id}")
    public int deleteDeptById(Integer id);

    @Insert("insert into department(departmentName) values (#{departmentName})")
    public int insertDepartment(Department department);

    @Update("update department set departmentName=#{departmentName} where id=#{id}")
    public int updateDept(Department department);
}

调用

@RestController
public class DepartmentController {
    @Autowired
    DepartmentMapper departmentMapper;
    @GetMapping("/dept{id}")
    public Department getDepartment(@PathVariable("id") Integer id){
        return departmentMapper.getDeptById(id);
    }
    @GetMapping("/dept")
    public int insertDept(Department department){
        return departmentMapper.insertDepartment(department);
    }
}

设置mybatisConfig

@RestController
public class DepartmentController {
    @Autowired
    DepartmentMapper departmentMapper;
    @GetMapping("/dept{id}")
    public Department getDepartment(@PathVariable("id") Integer id){
        return departmentMapper.getDeptById(id);
    }
    @GetMapping("/dept")
    public Department insertDept(Department department){
        departmentMapper.insertDepartment(department);
        return department;
    }
}

4、配置文件版

全局配置文件

<?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>

    <settings>
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
</configuration>

mapper映射文件

<?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.atguigu.springboot.mapper.EmployeeMapper">
    <!--    public Employee getEmpById(Integer id);
 
     public void insertEmp(Employee employee);-->
    <select id="getEmpById" resultType="com.atguigu.springboot.bean.Employee">
        SELECT * FROM employee WHERE id=#{id}
    </select>

    <insert id="insertEmp">
        INSERT INTO employee(lastName,email,gender,d_id) VALUES (#{lastName},#{email},#{gender},#{dId})
    </insert>
</mapper>

在application.yml中配置mybatis

mybatis:
  config-location: classpath:mybatis/mybatis-config.xml   指定全局配置文件位置
  mapper-locations: classpth:mybatis/mapper/*.xml         指定映射文件位置