<dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>3.5.6</version></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>5.1.47</version></dependency>

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mappernamespace="mapper.UserMapper"><insertid="addUser"parameterType="pojo.User">        insert into user(id, name, password)
        values (#{id}, #{name}, #{password})
</insert><deleteid="deleteUserById"parameterType="int">        delete
        from user
        where id = #{id}
</delete><updateid="updateUserById"parameterType="pojo.User">        update user
        set name=#{name},
            password = #{password}
        where id = #{id}
</update><selectid="selectUser"resultType="pojo.User">        select *
        from user
</select><selectid="selectUserByNameAndPassword"parameterType="map"resultType="pojo.User">        select *
        from user
        where name = #{name}
          and password = #{password}
</select></mapper>

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd"><configuration><propertiesresource="jdbc.properties"/><!--环境配置--><environmentsdefault="development"><environmentid="development"><transactionManagertype="JDBC"/><dataSourcetype="POOLED"><propertyname="driver"value="${driver}"/><propertyname="url"value="${url}"/><propertyname="username"value="${username}"/><propertyname="password"value="${password}"/></dataSource></environment></environments><!--注册 Mapper--><mappers><mapperclass="mapper.UserMapper"/></mappers></configuration>

<!--配置--><configuration><!--属性--><properties><!--设置--><settings><!--类型别名--><typeAliases><!--类型处理器--><typeHandlers><!--对象工厂--><objectFactory><!--插件--><plugins><!--环境配置--><environments><!--数据库厂商标识--><databaseIdProvider><!--映射器--><mappers></configuration><!-- 注意元素节点的顺序！顺序不对会报错 -->

url=jdbc:mysql://localhost:3306/mybatis?useUnicode=true&characterEncoding=utf8
driver=com.mysql.jdbc.Driver
username=root
password=123456

<propertiesresource="jdbc.properties"/><!--环境配置--><environmentsdefault="development"><environmentid="development"><transactionManagertype="JDBC"/><dataSourcetype="POOLED"><propertyname="driver"value="${driver}"/><propertyname="url"value="${url}"/><propertyname="username"value="${username}"/><propertyname="password"value="${password}"/></dataSource></environment></environments

<!--环境配置--><environmentsdefault="development"><environmentid="development"><transactionManagertype="JDBC"/><dataSourcetype="POOLED"><propertyname="driver"value="com.mysql.jdbc.Driver"/><propertyname="url"value="jdbc:mysql://localhost:3306/mybatis?useUnicode=true&amp;characterEncoding=utf8"/><propertyname="username"value="root"/><propertyname="password"value="123456"/></dataSource></environment></environments>

<settings><settingname="cacheEnabled"value="true"/><settingname="lazyLoadingEnabled"value="true"/><settingname="multipleResultSetsEnabled"value="true"/><settingname="useColumnLabel"value="true"/><settingname="useGeneratedKeys"value="false"/><settingname="autoMappingBehavior"value="PARTIAL"/><settingname="autoMappingUnknownColumnBehavior"value="WARNING"/><settingname="defaultExecutorType"value="SIMPLE"/><settingname="defaultStatementTimeout"value="25"/><settingname="defaultFetchSize"value="100"/><settingname="safeRowBoundsEnabled"value="false"/><settingname="mapUnderscoreToCamelCase"value="false"/><settingname="localCacheScope"value="SESSION"/><settingname="jdbcTypeForNull"value="OTHER"/><settingname="lazyLoadTriggerMethods"value="equals,clone,hashCode,toString"/></settings>

<typeAliases><typeAliastype="pojo.User"alias="User"/></typeAliases>

<typeAliases><packagename="pojo"/></typeAliases>

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mappernamespace="mapper.UserMapper"><deleteid="deleteUserById"parameterType="int">        delete
        from user
        where id = #{id}
</delete></mapper>

Map<String,Object> map = new HashMap<>();
map.put("name", "test");
map.put("password", "test");
User user = userMapper.selectUserByNameAndPassword(map);

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mappernamespace="mapper.UserMapper"><selectid="selectUserByNameAndPassword"parameterType="map"resultType="pojo.User">        select *
        from user
        where name = #{name}
          and password = #{password}
</select></mapper>

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mappernamespace="mapper.UserMapper"><insertid="addUser"parameterType="pojo.User">        insert into user(id, name, password)
        values (#{id}, #{name}, #{password})
</insert></mapper>

import org.apache.ibatis.annotations.Param;
public interface UserMapper {
    int deleteUserById(@Param("id") int id);
}

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mappernamespace="mapper.UserMapper"><deleteid="deleteUserById">        delete
        from user
        where id = #{id}
</delete></mapper>

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mappernamespace="mapper.UserMapper"><selectid="selectUserById"resultType="map">        select id , name , pwd
        from user
        where id = #{id}
</select></mapper>

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mappernamespace="mapper.UserMapper"><!-- 编写 resultMap --><resultMapid="UserMaps"type="pojo.User"><!-- id为主键 --><idcolumn="id"property="id"/><!-- column是数据库表的列名 , property是对应实体类的属性名 --><resultcolumn="name"property="name"/><resultcolumn="password"property="password"/></resultMap><!-- 返回值类型为 resultMap ，值为编写的 resultMap 的 id --><selectid="selectUser"resultMap="UserMaps">        select *
        from user
</select></mapper>

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mappernamespace="mapper.StudentMapper"><!--需求：获取所有学生及对应老师的信息--><!--思路1：嵌套查询association → 一个复杂类型的关联；使用它来处理关联查询--><selectid="getStudents"resultMap="StudentTeacher">        select * from student
</select><resultMapid="StudentTeacher"type="Student"><!--association关联属性 property→属性名 javaType→属性类型 column→关联列名 select→子查询--><associationproperty="teacher"column="tid"javaType="Teacher"select="getTeacher"/></resultMap><!-- 传递一个参数的时候，下面可以写任何值 --><selectid="getTeacher"resultType="teacher">        select * from teacher where id = #{id}
</select><!----------------------------------------------------------------------------------------------------><!--思路2：结果集的映射--><selectid="getStudents2"resultMap="StudentTeacher2">        select s.id sid, s.name sname , t.name tname
        from student s,teacher t
        where s.tid = t.id
</select><resultMapid="StudentTeacher2"type="Student"><idproperty="id"column="sid"/><resultproperty="name"column="sname"/><!--association关联属性 property→属性名 javaType→属性类型--><associationproperty="teacher"javaType="Teacher"><!-- column是数据库表的列名 , property是对应实体类的属性名 --><resultproperty="name"column="tname"/></association></resultMap></mapper>

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mappernamespace="mapper.StudentMapper"><selectid="getStudents"resultMap="StudentTeacher">        select * from student
</select><!-- 传递多个参数时association 中 column 多参数配置：column="{key=value,key=value}"其实就是键值对的形式，key 是传给下个 sql 的取值名称，value 是片段一中 sql 查询的字段名--><resultMapid="StudentTeacher"type="Student"><!--association关联属性 property→属性名 javaType→属性类型 column→关联列名 select→子查询--><associationproperty="teacher"column="{id=tid,name=tname}"javaType="Teacher"select="getTeacher"/></resultMap><selectid="getTeacher"resultType="teacher">        select * from teacher where id = #{id} and name = #{name}
</select></mapper>

<?xmlversion="1.0" encoding="UTF-8" ?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mappernamespace="mapper.TeacherMapper"><!--需求：获取指定老师，及老师下的所有学生--><!--思路1：嵌套查询--><selectid="getTeacher"resultMap="TeacherStudent2">        select * from teacher where id = #{id}
</select><resultMapid="TeacherStudent2"type="Teacher"><!--column是 student 表外键的列名--><collectionproperty="students"javaType="ArrayList"ofType="Student"column="id"select="getStudentByTeacherId"/></resultMap><selectid="getStudentByTeacherId"resultType="Student">        select * from student where tid = #{id}
</select><!----------------------------------------------------------------------------------------------------><!--思路2:结果集映射集合映射使用 collection！JavaType 和 ofType都是用来指定对象类型的JavaType是用来指定 pojo 中属性的类型ofType 指定的是映射到 list集合属性中 pojo的类型。--><selectid="getTeacher"resultMap="TeacherStudent">        select s.id sid, s.name sname , t.name tname, t.id tid
        from student s,teacher t
        where s.tid = t.id and t.id=#{id}
</select><resultMapid="TeacherStudent"type="Teacher"><resultproperty="name"column="tname"/><collectionproperty="students"ofType="Student"><resultproperty="id"column="sid"/><resultproperty="name"column="sname"/><resultproperty="tid"column="tid"/></collection></resultMap></mapper>

<!--如果名字为空，那么只根据密码查询，反之，则根据名字来查询select * from blog where name = #{name} and password = #{password}--><selectid="selectUserByNameAndPassword"parameterType="map"resultType="pojo.User">    select *
    from user
    where
<iftest="name!=null">        name = #{name}
</if><iftest="password!=null">        and password = #{password}
</if></select>

<!--如果名字为空，那么只根据密码查询，反之，则根据名字来查询select * from blog where name = #{name} and password = #{password}--><selectid="selectUserByNameAndPassword"parameterType="map"resultType="pojo.User">    select *
    from user
<where><iftest="name != null">            name = #{name}
</if><iftest="password != null">            and password = #{password}
</if></where></select>

<!--update user set name=#{name},password=#{password} where id=#{id}--><updateid="updateUserById"parameterType="pojo.User">    update user
<set><iftest="name!=null">            name=#{name},
</if><iftest="password!=null">            password = #{password}
</if></set>    where id = #{id}
</update>

<selectid="selectUserByNameAndPassword"parameterType="map"resultType="pojo.User">    select *
    from user
<where><choose><whentest="name != null">                name = #{name}
</when><whentest="password != null">                and password = #{password}
</when><otherwise>                and id=#{id}
</otherwise></choose></where></select>

<!--select * from user where id in (1,2,3)--><selectid="selectUser"resultType="pojo.User">    select *
    from user
    where id in
<!--List 实例将会以 "list" 作为键数组实例的键是 "array"--><foreachcollection="array"item="id"open="("separator=","close=")">        #{id}
</foreach></select>

<sqlid="if-name-password"><iftest="name != null">        name = #{name}
</if><iftest="password != null">        and password = #{password}
</if></sql>

<selectid="selectUserByNameAndPassword"parameterType="map"resultType="pojo.User">  select * from user
<where><!-- 引用 sql 片段，如果 refid 指定的不在本文件中，那么需要在前面加上 namespace --><includerefid="if-name-password"></include><!-- 在这里还可以引用其他的 sql 片段 --></where></select>

<settings><settingname="logImpl"value="STDOUT_LOGGING"/></settings>

<dependency><groupId>log4j</groupId><artifactId>log4j</artifactId><version>1.2.17</version></dependency>

#将等级为DEBUG的日志信息输出到console和file这两个目的地，console和file的定义在下面的代码
log4j.rootLogger=DEBUG,console,file
#控制台输出的相关设置
log4j.appender.console = org.apache.log4j.ConsoleAppender
log4j.appender.console.Target = System.out
log4j.appender.console.Threshold=DEBUG
log4j.appender.console.layout = org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=[%c]-%m%n
#文件输出的相关设置
log4j.appender.file=utils.MyDailyRollingFileAppender
#日志文件路径
log4j.appender.file.File=./logs/log.log
log4j.appender.file.Encoding=utf-8
log4j.appender.file.Append=true
log4j.appender.file.Threshold=DEBUG
log4j.appender.file.layout=org.apache.log4j.PatternLayout
#设置日志文件名为日期并按天生成日志文件
log4j.appender.file.datePattern = '.'yyyy-MM-dd
#保留7天的日志文件
log4j.appender.file.maxBackupIndex=7
log4j.appender.file.layout.ConversionPattern=[%d{yyyy-MM-dd HH:mm:ss,SSS}][%c]%m%n
#日志输出级别
log4j.logger.org.mybatis=DEBUG
log4j.logger.java.sql=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.ResultSet=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG

<settingname="cacheEnabled"value="true"/>

<cache/>

<cacheeviction="FIFO"flushInterval="60000"size="512"readOnly="true"/>

<!--每一个 Mapper.xml 都需要再 Mybatis 核心配置文件中注册--><mappers><!--使用相对于类路径的资源引用--><mapperresource="mapper/UserMapper.xml"/><!--使用映射器接口实现类的完全限定类名--><mapperclass="mapper.UserMapper"/><!--将包内的映射器接口实现全部注册为映射器 --><packagename="mapper"/></mappers>

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