mybatis学习笔记（二）增删改查

作为持久层框架，mybaits作用和hibernate一样，无非就是对数据库进行增删改查操作，下面我们通过4个实例感受一下。其实也就是增删改查，掌握这些，基本上就掌握了mybatis的基本操作了，下面一个个模块来完成。
先看下工程整体内容：

在这个工程下将完成增删改查代码演示。
　　
1 mybatis核心配置文件

<?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>           <!-- changes from the defaults for testing -->           <setting name="cacheEnabled" value="false" />           <setting name="useGeneratedKeys" value="true" />           <setting name="defaultExecutorType" value="REUSE" />       </settings>    <typeAliases>          <typeAlias alias="TbUser" type="org.liyb.mybatis.model.TbUser"/>       </typeAliases>    <environments default="development">          <environment id="development">              <transactionManager type="jdbc"/>              <dataSource type="POOLED">                 <property name="driver" value="com.mysql.jdbc.Driver"/>                 <property name="url" value="jdbc:mysql://localhost:3306/springstud"/>                 <property name="username" value="mysql"/>                 <property name="password" value="mysql"/>              </dataSource>          </environment>       </environments>       <mappers>           <mapper resource="org/liyb/mybatis/dao/TbUserMapper.xml" />       </mappers>   </configuration>

　　以上这些环境配置（标签中的内容在以后和spring整合后，都会交给Spring来管理，现在暂时交给 mybatis来管理）中，修改成自己数据库相对应的情况即可，标签用来配置映射文件的，这些映射文件是针对不同的pojo的，这个示例中只操作一个User对象，所以只有一个配置文件，在sqlmap目录下的TbUserMapper.xml，在下文中可以看到。最后来看一下整个环境的结构：

1. 程序的编写

   　　创建pojo类：
   　　

package org.liyb.mybatis.model;public class TbUser {    private String uname;    private String name;    private String phone;    private String password;    public String getUname() {        return uname;    }    public void setUname(String uname) {        this.uname = uname;    }    ...

插入用户数据

<?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="org.liyb.mybatis.dao.TbUserMapper" >    <resultMap id="BaseResultMap" type="org.liyb.mybatis.model.TbUser" >        <id column="uname" property="uname" jdbcType="VARCHAR" />        <result column="name" property="name" jdbcType="VARCHAR" />        <result column="phone" property="phone" jdbcType="VARCHAR" />        <result column="password" property="password" jdbcType="VARCHAR" />    </resultMap>    <!-- 20160523 增添用户-->    <insert id="insertUser" parameterType="org.liyb.mybatis.model.TbUser" >        insert into tb_user (uname, name, phone, password)            values        (#{uname,jdbcType=VARCHAR}, #{name,jdbcType=VARCHAR}, #{phone,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR})    </insert></mapper>

根据用户姓名查询用户信息

<?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="org.liyb.mybatis.dao.TbUserMapper" >    <resultMap id="BaseResultMap" type="org.liyb.mybatis.model.TbUser" >        <id column="uname" property="uname" jdbcType="VARCHAR" />        <result column="name" property="name" jdbcType="VARCHAR" />        <result column="phone" property="phone" jdbcType="VARCHAR" />        <result column="password" property="password" jdbcType="VARCHAR" />    </resultMap>    <!-- 20160523 增添用户-->    <insert id="insertUser" parameterType="org.liyb.mybatis.model.TbUser" >        insert into tb_user (uname, name, phone, password)            values        (#{uname,jdbcType=VARCHAR}, #{name,jdbcType=VARCHAR}, #{phone,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR})    </insert>    <!-- 根据name查询 -->    <select id="selectByPrimaryKey" parameterType="String" resultType="org.liyb.mybatis.model.TbUser">        select * from tb_user where uname = #{name}    </select></mapper>

修改用户信息

<?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="org.liyb.mybatis.dao.TbUserMapper" >    <resultMap id="BaseResultMap" type="org.liyb.mybatis.model.TbUser" >        <id column="id" property="uname" jdbcType="VARCHAR" />        <result column="name" property="name" jdbcType="VARCHAR" />        <result column="phone" property="phone" jdbcType="VARCHAR" />        <result column="password" property="password" jdbcType="VARCHAR" />    </resultMap>    <!-- 20160523 增添用户-->    <insert id="insertUser" parameterType="TbUser" >        insert into tb_user (id, name, phone, password)            values        (#{id,jdbcType=VARCHAR}, #{name,jdbcType=VARCHAR}, #{phone,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR})    </insert>    <!-- 根据name查询 -->    <select id="selectByUserName" parameterType="String" resultType="org.liyb.mybatis.model.TbUser">        select * from tb_user where id = #{name}    </select>    <!-- 修改用户名称 -->    <update id="updateByUserName" parameterType="TbUser">        update tb_user set name=#{name},phone=#{phone},password=#{password} where id=#{id}    </update></mapper>

删除用户：

<?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="org.liyb.mybatis.dao.TbUserMapper" >    <resultMap id="BaseResultMap" type="org.liyb.mybatis.model.TbUser" >        <id column="id" property="uname" jdbcType="VARCHAR" />        <result column="name" property="name" jdbcType="VARCHAR" />        <result column="phone" property="phone" jdbcType="VARCHAR" />        <result column="password" property="password" jdbcType="VARCHAR" />    </resultMap>    <!-- 20160523 增添用户-->    <insert id="insertUser" parameterType="TbUser" >        insert into tb_user (id, name, phone, password)            values        (#{id,jdbcType=VARCHAR}, #{name,jdbcType=VARCHAR}, #{phone,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR})    </insert>    <!-- 根据name查询 -->    <select id="selectByUserName" parameterType="String" resultType="org.liyb.mybatis.model.TbUser">        select * from tb_user where id = #{name}    </select>    <!-- 修改用户名称 -->    <update id="updateByUserName" parameterType="TbUser">        update tb_user set name=#{name},phone=#{phone},password=#{password} where id=#{id}    </update>        <!-- 根据用户id删除用户信息 -->    <update id="deleteUserById" parameterType="String">        delete from tb_user where id=#{id}    </update></mapper>

至此增删改产全部实现，下面贴出全部代码。

mybatis-config.xml

<?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>           <!-- changes from the defaults for testing -->           <setting name="cacheEnabled" value="false" />           <setting name="useGeneratedKeys" value="true" />           <setting name="defaultExecutorType" value="REUSE" />       </settings>    <typeAliases>          <typeAlias alias="TbUser" type="org.liyb.mybatis.model.TbUser"/>       </typeAliases>    <environments default="development">          <environment id="development">              <transactionManager type="jdbc"/>              <dataSource type="POOLED">                 <property name="driver" value="com.mysql.jdbc.Driver"/>                 <property name="url" value="jdbc:mysql://localhost:3306/springstud"/>                 <property name="username" value="mysql"/>                 <property name="password" value="mysql"/>              </dataSource>          </environment>       </environments>       <mappers>           <mapper resource="org/liyb/mybatis/dao/TbUserMapper.xml" />       </mappers>   </configuration>

TbUserMapper.java

package org.liyb.mybatis.dao;import org.liyb.mybatis.model.TbUser;public interface TbUserMapper {    TbUser selectByUserName(String uname);    int updateByUserName(TbUser user);    public void insertUser(TbUser user);    public TbUser getUser(String name);    void deleteUserById(String id);}

TbUserMapper.xml

<?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>           <!-- changes from the defaults for testing -->           <setting name="cacheEnabled" value="false" />           <setting name="useGeneratedKeys" value="true" />           <setting name="defaultExecutorType" value="REUSE" />       </settings>    <typeAliases>          <typeAlias alias="TbUser" type="org.liyb.mybatis.model.TbUser"/>       </typeAliases>    <environments default="development">          <environment id="development">              <transactionManager type="jdbc"/>              <dataSource type="POOLED">                 <property name="driver" value="com.mysql.jdbc.Driver"/>                 <property name="url" value="jdbc:mysql://localhost:3306/springstud"/>                 <property name="username" value="mysql"/>                 <property name="password" value="mysql"/>              </dataSource>          </environment>       </environments>       <mappers>           <mapper resource="org/liyb/mybatis/dao/TbUserMapper.xml" />       </mappers>   </configuration>

TbUser.java

package org.liyb.mybatis.model;public class TbUser {    private String id;    private String name;    private String phone;    private String password;    public TbUser(){    }    public String getId() {        return id;    }    public void setId(String id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getPhone() {        return phone;    }    public void setPhone(String phone) {        this.phone = phone;    }    public String getPassword() {        return password;    }    public void setPassword(String password) {        this.password = password;    }    public TbUser(String id,String name,String phone,String password){        this.id = id;        this.name = name;        this.phone = phone;        this.password = password;    }}

测试类：

package test.mybatis;import org.apache.ibatis.session.SqlSession;import org.apache.ibatis.session.SqlSessionFactory;import org.liyb.mybatis.dao.TbUserMapper;import org.liyb.mybatis.model.TbUser;public class TestMyBatis {    public static SqlSessionFactory sqlSessionFactory = null;    static{        sqlSessionFactory = MyBatisUtil.getSqlsessionfactory();    }    /**     *      *author: lee by 2016年6月20日     *description：mybatis插入用户数据     *@param      *@return void     */    public static void testAdd() {        SqlSession sqlSession = sqlSessionFactory.openSession();        try {            TbUserMapper userMapper = sqlSession.getMapper(TbUserMapper.class);            TbUser user = new TbUser("liybk", "liyb","18601387505","123");            userMapper.insertUser(user);            sqlSession.commit();// 这里一定要提交，不然数据进不去数据库中            } finally {                sqlSession.close();            }    }    /**     *      *author: lee by 2016年6月20日     *description：mybatis根据姓名查询用户     *@param      *@return void     */    public static void testQuery(String name){        SqlSession sqlSession = sqlSessionFactory.openSession();        try{            TbUserMapper userMapper = sqlSession.getMapper(TbUserMapper.class);            TbUser users = userMapper.selectByUserName(name);            System.out.println("该用户的姓名是："+users.getName()+" ,手机号码为："+users.getPhone());        }finally{            sqlSession.close();        }    }    public static void testUpdate(String id){        SqlSession sqlSession = sqlSessionFactory.openSession();        try{            TbUserMapper userMapper = sqlSession.getMapper(TbUserMapper.class);            TbUser user = userMapper.selectByUserName(id);            user.setName("songzhihui3");            int count = userMapper.updateByUserName(user);            sqlSession.commit();            System.out.println(count);        }finally{            sqlSession.close();        }    }    public static void testDelete(String id){        SqlSession sqlSession = sqlSessionFactory.openSession();        try{            TbUserMapper userMapper = sqlSession.getMapper(TbUserMapper.class);            userMapper.deleteUserById(id);            sqlSession.commit();        }finally{            sqlSession.close();        }    }    public static void main(String[] args){        //TestMyBatis.testAdd();        //TestMyBatis.testQuery("liybk");        //TestMyBatis.testUpdate("songzh2");        TestMyBatis.testDelete("songzh2");    }}

基于maven工程的pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">  <modelVersion>4.0.0</modelVersion>  <groupId>org.liyb.mybatis.stud</groupId>  <artifactId>mybatisHelloWorld</artifactId>  <version>0.0.1-SNAPSHOT</version>  <packaging>war</packaging>  <dependencies>    <dependency>        <groupId>org.mybatis</groupId>        <artifactId>mybatis</artifactId>        <version>3.4.0</version>    </dependency>    <dependency>        <groupId>org.mybatis.generator</groupId>        <artifactId>mybatis-generator-core</artifactId>        <version>1.3.2</version>    </dependency>    <dependency>        <groupId>mysql</groupId>        <artifactId>mysql-connector-java</artifactId>        <version>5.1.38</version>    </dependency>  </dependencies>  <build>    <plugins>        <plugin>            <groupId>org.apache.maven.plugins</groupId>            <artifactId>maven-compiler-plugin</artifactId>                <configuration>                    <source>1.7</source>                    <target>1.7</target>                    <encoding>UTF-8</encoding>            </configuration>        </plugin>        <!-- mybatis-generator -->        <plugin>            <groupId>org.mybatis.generator</groupId>            <artifactId>mybatis-generator-maven-plugin</artifactId>            <version>1.3.2</version>                <configuration>                    <verbose>true</verbose>                    <overwrite>true</overwrite>                </configuration>         </plugin>    </plugins>  </build></project>