> 文档中心 > Mybatis-1基本实现

Mybatis-1基本实现

文章目录

  • 一、编码流程
    • 1、新建Bean类
    • 2、导入对应的maven依赖
    • 3、建立Mapper映射文件
    • 4、配置文件
    • 5、测试类
  • 二、通过接口实现
    • 1、新建Xs0101Mapper接口
    • 2、映射文件调整
    • 3、测试类
  • 三、注意事项
    • 1、数据库实体类字段不一致
  • 四、配置文件详解
    • 1、configuration.xml
      • 1.1properties
      • 1.2typeAliases
      • 1.3mappers

一、编码流程

1、新建Bean类

package com.web.bean;import lombok.Data;@Datapublic class Xs0101 {  private String xs0101Id;  private String xh;  private String xm;  private String age;  private String address;}

2、导入对应的maven依赖

引入Mybatis和Oracle的依赖

<dependencies><dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>3.3.0</version></dependency><dependency><groupId>com.oracle</groupId><artifactId>ojdbc6</artifactId><version>11.2.0.1.0</version></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.18.24</version></dependency></dependencies>

处理配置文件读取问题

<build><resources><resource><directory>src/main/java</directory><includes><include>**/*.properties</include><include>**/*.xml</include></includes><filtering>false</filtering></resource><resource><directory>src/main/resources</directory><includes><include>**/*.properties</include><include>**/*.xml</include></includes><filtering>false</filtering></resource></resources></build>

3、建立Mapper映射文件

新建mapper包,在mapper包下新建Xs0101Mapper.xml,管理SQL

<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mapper namespace="xs0101">        <select id="findXs0101ById" parameterType="java.lang.String" resultType="com.web.bean.Xs0101"> SELECT * FROM xs0101 WHERE xs0101Id = #{id}    </select></mapper>

4、配置文件

在resources下新建configuration.xml,用于管理数据源,Mapper映射文件

<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"><configuration>    <environments default="development"> <environment id="development">          <transactionManager type="JDBC"/>          <dataSource type="POOLED">  <property name="driver" value="oracle.jdbc.driver.OracleDriver" />  <property name="url" value="jdbc:oracle:thin:@localhost:1521:orcl" />  <property name="username" value="scott" />  <property name="password" value="123456" />     </dataSource> </environment>    </environments>    <mappers> <!-- 标签用来配置映射文件的,可以有多个 --> <mapper resource="com/web/mapper/Xs0101Mapper.xml" />    </mappers></configuration>

5、测试类

public static void main(String[] args) {    //读取配置文件    InputStream inputStream = null;    try { inputStream = Resources.getResourceAsStream("configuration.xml");    } catch (IOException e) { e.printStackTrace();    }    //创建SqlSession工厂    SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(inputStream);    //打开sqlSession,默认是不提交事务,带参数true后自动提交    SqlSession sqlSession = factory.openSession(true);    //通过namespace.id的方式进行调用    Xs0101 xs0101 = sqlSession.selectOne("xs0101.findXs0101ById","1007");    System.out.println(xs0101);    //提交回滚事务    //sqlSession.commit();    //sqlSession.rollback();    //关闭连接    sqlSession.close();}

二、通过接口实现

1、新建Xs0101Mapper接口

package com.web.mapper;import com.web.bean.Xs0101;public interface Xs0101Mapper {    public Xs0101 findXs0101ById(String is);}

2、映射文件调整

Mapper映射文件中的namespace值更改为接口的权限名,SQL标签的id和接口的方法名保持一致
Mybatis-1基本实现

3、测试类

Mybatis-1基本实现

三、注意事项

1、数据库实体类字段不一致

Mybatis-1基本实现
1)通过别名处理

<select id="findXs0101ById" parameterType="java.lang.String" resultType="com.web.bean.Xs0101">   SELECT xs_0101id xs0101id,xh,xm,age,address FROM xs0101 WHERE xs_0101id = #{id}</select>

2)通过映射配置

<mapper namespace="xs0101">    <resultMap id="Xs0101Map" type="com.web.bean.Xs0101"> <id column="xs_0101id" property="xs0101id"/> <id column="xh" property="xh"/> <id column="age" property="age"/> <id column="address" property="address"/>    </resultMap>        <select id="findXs0101ById" parameterType="java.lang.String" resultType="com.web.bean.Xs0101"> SELECT xs_0101id,xh,xm,age,address FROM xs0101 WHERE xs_0101id = #{id}    </select></mapper>

四、配置文件详解

1、configuration.xml

1.1properties

新建dbconfig.properties
Mybatis-1基本实现
configuration.xml
Mybatis-1基本实现

1.2typeAliases

建议写权限名
Mybatis-1基本实现
Mybatis-1基本实现

1.3mappers

Mybatis-1基本实现