Spring入门（四）——整合Mybatis

• 2020 年 3 月 11 日
• 筆記

1. 准备jar包及目录结构

2. 配置db.properties

driver = com.mysql.jdbc.Driver  url = jdbc:mysql://127.0.0.1:3306/Howl  name = root  password =

3. 配置applicationContext.xml

<!-- 加载配置文件 -->  <context:property-placeholder location="classpath:db.properties" />      <!--spring自带数据源,没有连接池功能 -->  <!-- <bean id="DataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">      <property name="driverClassName" value="${driver}"></property>      <property name="url" value="${url}"></property>      <property name="username" value="${name}"></property>      <property name="password" value="${password}"></property>  </bean> -->      <!-- c3p0数据源，推荐 -->  <bean id="DataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">      <property name="driverClass" value="${driver}"/>      <property name="jdbcUrl" value="${url}"/>      <property name="user" value="${name}"/>      <property name="password" value="${password}"/>  </bean>      <!-- 配置SqlSessionFactory,加载mybaits配置文件和映射文件 -->  <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">      <property name="configLocation" value="classpath:mybatis.xml"/>      <property name="dataSource" ref="DataSource"/>  </bean>

4. 创建Bean对象

package bean;    public class User {        private int id;      private String name;      private String password;        public int getId() {          return id;      }      public void setId(int id) {          this.id = id;      }      public String getName() {          return name;      }      public void setName(String name) {          this.name = name;      }      public String getPassword() {          return password;      }      public void setPassword(String password) {          this.password = password;      }      @Override      public String toString() {          return "User [id=" + id + ", name=" + name + ", password=" + password + "]";      }  }

5. 配置Mapper.xml文件（Mapper代理方式）

<mapper namespace="com.howl.UserMapper">        <!-- 通过id查询用户 -->      <select id="findUserById" parameterType="Integer" resultType="bean.User">          select * from user where id = #{id}      </select>    </mapper>

6. 代理接口

package com.howl;    public interface UserMapper {        public User findUserById(int id);    }

7. 配置Mybatis.xml

<!-- 根标签 -->  <configuration>        <!-- 引入mapper文件的位置 -->      <mappers>          <mapper resource="Mapper/UserMapper.xml"/>      </mappers>    </configuration>

8. 测试

//获取sqlSession  ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml");  SqlSessionFactory sqlSessionFactory = (SqlSessionFactory ) ac.getBean("sqlSessionFactory");  SqlSession sqlSession = sqlSessionFactory.openSession();    //获取代理对象  UserMapper userMapper = sqlSession.getMapper(com.howl.UserMapper.class);  User user = userMapper.findUserById(46);    //打印Bean对象  System.out.println(user);

9. 打印

<!-- 整合成功 -->  <!-- 十二月 04, 2019 8:30:35 下午 com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource -->    User [id=46, name=123123, password=123123]