MyBatis

Posted 2020-10-05 关键步就几步

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1、搭建框架

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5">
  <display-name></display-name>
  
  	<welcome-file-list>
		<welcome-file>index.html</welcome-file>
	</welcome-file-list>
	
	<context-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>classpath:spring/applicationContext-*.xml</param-value>
	</context-param>
	<listener>
		<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
	</listener>
  
  	<!-- 解决post乱码 -->
	<filter>
		<filter-name>CharacterEncodingFilter</filter-name>
		<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
		<init-param>
			<param-name>encoding</param-name>
			<param-value>utf-8</param-value>
		</init-param>
	</filter>
	<filter-mapping>
		<filter-name>CharacterEncodingFilter</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
  
  
  <!-- springmvc的前端控制器 -->
	<servlet>
		<servlet-name>Springmvc</servlet-name>
		<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
		<!-- contextConfigLocation不是必须的， 如果不配置contextConfigLocation， springmvc的配置文件默认在：WEB-INF/servlet的name+"-servlet.xml" -->
		<init-param>
			<param-name>contextConfigLocation</param-name>
			<param-value>classpath:spring/springmvc.xml</param-value>
		</init-param>
		<load-on-startup>1</load-on-startup>
	</servlet>
	<servlet-mapping>
		<servlet-name>Springmvc</servlet-name>
		<!-- 伪静态化 -->
		<url-pattern>*.html</url-pattern>
	</servlet-mapping>
  
   
   
  
  
</web-app>

Springmvc

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
	xmlns:mvc="http://www.springframework.org/schema/mvc"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd		
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.2.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd">
	
	<context:component-scan base-package="com.cb.web" />
	<mvc:annotation-driven />
	<bean
		class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<property name="prefix" value="/WEB-INF/jsp/" />
		<property name="suffix" value=".jsp" />
	</bean>
	
</beans>

spring-service

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p"
	xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
	http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd
	http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.2.xsd
	http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.2.xsd">

	<!-- 配置包扫描器 -->
	<context:component-scan base-package="com.cb.service"/>
	 
</beans>

spring-transaction

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p"
	xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
	http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd
	http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.2.xsd
	http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.2.xsd">
	<!-- 事务管理器 -->
	<bean id="transactionManager"
		class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
		<!-- 数据源 -->
		<property name="dataSource" ref="dataSource" />
	</bean>
	<!-- 通知 -->
	<tx:advice id="txAdvice" transaction-manager="transactionManager">
		<tx:attributes>
			<!-- 传播行为 -->
			<tx:method name="save*" propagation="REQUIRED" />
			<tx:method name="insert*" propagation="REQUIRED" />
			<tx:method name="add*" propagation="REQUIRED" />
			<tx:method name="create*" propagation="REQUIRED" />
			<tx:method name="delete*" propagation="REQUIRED" />
			<tx:method name="update*" propagation="REQUIRED" />
			<tx:method name="find*" propagation="SUPPORTS" read-only="true" />
			<tx:method name="select*" propagation="SUPPORTS" read-only="true" />
			<tx:method name="get*" propagation="SUPPORTS" read-only="true" />
		</tx:attributes>
	</tx:advice>
	<!-- 切面 -->
	<aop:config>
		<aop:advisor advice-ref="txAdvice"
			pointcut="execution(* com.cb.service..*.*(..))" />
	</aop:config>
</beans>

spring-mapper

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p"
	xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
	http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd
	http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.2.xsd
	http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.2.xsd">

	<!-- 数据库连接池 -->
	<!-- 加载配置文件 -->
	<context:property-placeholder location="classpath:conf/db.properties" />
	<!-- 数据库连接池 -->
	<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource"
		destroy-method="close">
		<property name="url" value="${jdbc.url}" />
		<property name="username" value="${jdbc.username}" />
		<property name="password" value="${jdbc.password}" />
		<property name="driverClassName" value="${jdbc.driver}" />
		<property name="maxActive" value="10" />
		<property name="minIdle" value="5" />
	</bean>
	<!-- 让spring管理sqlsessionfactory 使用mybatis和spring整合包中的 -->
	<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
		<!-- 数据库连接池 -->
		<property name="dataSource" ref="dataSource" />
		<!-- 加载mybatis的全局配置文件 -->
		<property name="configLocation" value="classpath:mybatis/SqlMapConfig.xml" />
	</bean>
	<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
		<property name="basePackage" value="com.cb.mapper" />
	</bean>
</beans>

MyBatis需要一个SqlMapConfig.xml，哪怕是空的

<?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>
 

</configuration>

2、生成Mapper接口和Mapper配置文件，以及POJO

package com.cb.mapper;

import com.cb.pojo.Student;

public interface StudentMapper {
    int deleteByPrimaryKey(Integer stuid);

    int insert(Student record);

    int insertSelective(Student record);

    Student selectByPrimaryKey(Integer stuid);

    int updateByPrimaryKeySelective(Student record);

    int updateByPrimaryKey(Student record);
}

//===========================================
<?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.cb.mapper.StudentMapper" >
  <resultMap id="BaseResultMap" type="com.cb.pojo.Student" >
    <id column="stuID" property="stuid" jdbcType="INTEGER" />
    <result column="name" property="name" jdbcType="VARCHAR" />
    <result column="age" property="age" jdbcType="INTEGER" />
  </resultMap>
  <sql id="Base_Column_List" >
    stuID, name, age
  </sql>
  <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
    select 
    <include refid="Base_Column_List" />
    from student
    where stuID = #{stuid,jdbcType=INTEGER}
  </select>
  <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >
    delete from student
    where stuID = #{stuid,jdbcType=INTEGER}
  </delete>
  <insert id="insert" parameterType="com.cb.pojo.Student" >
    insert into student (stuID, name, age
      )
    values (#{stuid,jdbcType=INTEGER}, #{name,jdbcType=VARCHAR}, #{age,jdbcType=INTEGER}
      )
  </insert>
  <insert id="insertSelective" parameterType="com.cb.pojo.Student" >
    insert into student
    <trim prefix="(" suffix=")" suffixOverrides="," >
      <if test="stuid != null" >
        stuID,
      </if>
      <if test="name != null" >
        name,
      </if>
      <if test="age != null" >
        age,
      </if>
    </trim>
    <trim prefix="values (" suffix=")" suffixOverrides="," >
      <if test="stuid != null" >
        #{stuid,jdbcType=INTEGER},
      </if>
      <if test="name != null" >
        #{name,jdbcType=VARCHAR},
      </if>
      <if test="age != null" >
        #{age,jdbcType=INTEGER},
      </if>
    </trim>
  </insert>
  <update id="updateByPrimaryKeySelective" parameterType="com.cb.pojo.Student" >
    update student
    <set >
      <if test="name != null" >
        name = #{name,jdbcType=VARCHAR},
      </if>
      <if test="age != null" >
        age = #{age,jdbcType=INTEGER},
      </if>
    </set>
    where stuID = #{stuid,jdbcType=INTEGER}
  </update>
  <update id="updateByPrimaryKey" parameterType="com.cb.pojo.Student" >
    update student
    set name = #{name,jdbcType=VARCHAR},
      age = #{age,jdbcType=INTEGER}
    where stuID = #{stuid,jdbcType=INTEGER}
  </update>
</mapper>

//===========================================
package com.cb.pojo;

public class Student {
    private Integer stuid;

    private String name;

    private Integer age;

    public Integer getStuid() {
        return stuid;
    }

    public void setStuid(Integer stuid) {
        this.stuid = stuid;
    }

   
	public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name == null ? null : name.trim();
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }
    
    @Override
   	public String toString() {
   		return "Student [stuid=" + stuid + ", name=" + name + ", age=" + age + "]";
   	}

}

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