<context:property-placeholder location="classpath:jdbc.properties" />

<bean id="datasource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">

  <property name="driverClass" value="${jdbc.driver}" />

  <property name="jdbcUrl" value="${jdbc.url}" />

  <property name="user" value="${jdbc.username}" />

  <property name="password" value="${jdbc.password}" />

  <!-- 当连接池中的连接耗尽的时候c3p0一次同时获取的连接数 -->

  <property name="acquireIncrement" value="${jdbc.pool.increment}"/>

  <!-- 初始连接池大小 -->

  <property name="initialPoolSize" value="${jdbc.pool.init}"/>

  <!-- 连接池中连接最小个数 -->

  <property name="minPoolSize" value="${jdbc.pool.min}"/>

  <!-- 连接池中连接最大个数 -->

  <property name="maxPoolSize" value="${jdbc.pool.max}"/>

</bean>

<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">

  <property name="dataSource" ref="datasource"/>

  <!--    指定*Mapper.xml位置-->

  <property name="mapperLocations" value="classpath:mapper/*.xml" />

</bean>

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer" >

  <!--    指定的是接口（Java）路径-->

  <property name="basePackage" value="com.blueStarWei.mapper" />

  <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" />

</bean>

<!-- 声明式事务管理 : 定义事物管理器，由spring管理事务 -->

<tx:annotation-driven/>

<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">

  <property name="dataSource" ref="datasource"/>

</bean>

jdbc.driver=com.mysql.jdbc.Driver

jdbc.url=jdbc:mysql://127.0.0.1:3306/wei_db

jdbc.username=root

jdbc.password=root

#pool settings

jdbc.pool.init=10

jdbc.pool.increment=3

jdbc.pool.min=5

jdbc.pool.max=20

package com.blueStarWei.mapper;

import com.blueStarWei.bean.Person;

public interface PersonMapper {

    int addPerson(Person person);

    String getName(int id);

    Person getPersonById(int id);

}

5， 创建PersonMapper.xml【resources/mapper路径下】

<?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.blueStarWei.mapper.PersonMapper" >

  <insert id="addPerson" >

    insert into person(id,name,age,address) values(#{id},#{name},#{age},#{address})

  </insert>

  <select id="getName" parameterType="int" resultType="java.lang.String">

    select name from person where id = #{id}

  </select>

  <select id="getPersonById" parameterType="int" resultType="com.blueStarWei.bean.Person" >

    select * from person where id = #{id}

  </select>

</mapper>

6，修改controller【java路径下】

package com.blueStarWei.controller;

import com.blueStarWei.mapper.PersonMapper;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.PathVariable;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;

@RestController

@RequestMapping("/hello")

public class HelloWorld {

    @Autowired

    private PersonMapper person;

    @RequestMapping("/name/{id}")

    public String say(@PathVariable int id){

        return person.getName(id);

    }

}

备注：

如果*Mapper.xml放置在src/main/java路径下，需要在pom.xml种添加如下配置。（IDEA默认只编译resources下的xml文件）

<!-- 促使IDEA编译src/main/java路径下的xml-->

<build>

  <resources>

    <resource>

      <directory>src/main/java</directory>

      <includes>

        <include>**/*.xml</include>

      </includes>

    </resource>

  </resources>

</build>