mybatis笔记1 基本的配置和操做

mybatis比较轻量，适合开发比较小型的或者业务比较复杂的系统；

相对于hibernate来讲能够灵活的写sql，更灵活的处理遇到的业务逻辑；

能够说hibernate是pojo实体对db的orm映射，而mybatis是pojo对sql的映射；

做为入门，先不考虑高级的特性，速度来一个CRUD再从源码和一个具体的业务来研究它的原理和高级特性；

 

CRUD基本思路：做为一种比较流行的持久层ORM框架，至关于三层架构中的dao层；

最终做为程序员的咱们使用的SqlSession对象，先来个思路，再来个实现，最后研究细节；

 

环境准备，结合springmvc,作一个对博客文章的crud,下面贴出配置文件先；

第一列是依赖文件，都是在仓库中找到的最新的来用，兼容性如何暂且无论，先把简单的例子弄出来是关键；

第二列是web.xml的配置文件，定义一个spring的容器和mvc的url代理servlet；

第三列才是mybatis的使用环境准备，结合上图，上下往上推导定义出SqlSessionFactory,再定义出datasource和mapper配置文件；

第四列是springmvc的配置文件，至关常见，这里不解释；

<dependency>      <groupId>org.springframework</groupId>      <artifactId>spring-webmvc</artifactId>      <version>4.0.1.RELEASE</version> </dependency>      <dependency>          <groupId>org.springframework</groupId>          <artifactId>spring-jdbc</artifactId>          <version>4.0.1.RELEASE</version>      </dependency>      <dependency>          <groupId>org.mybatis</groupId>          <artifactId>mybatis</artifactId>          <version>3.2.4</version>      </dependency>      <dependency>          <groupId>org.mybatis</groupId>          <artifactId>mybatis-spring</artifactId>          <version>1.2.2</version>      </dependency>      <!-- 数据源和jdbc驱动依赖 start-->      <dependency>          <groupId>commons-dbcp</groupId>          <artifactId>commons-dbcp</artifactId>          <version>1.4</version>      </dependency>      <dependency>          <groupId>commons-pool</groupId>          <artifactId>commons-pool</artifactId>          <version>1.6</version>      </dependency>      <dependency>          <groupId>mysql</groupId>          <artifactId>mysql-connector-java</artifactId>          <version>5.1.29</version>      </dependency>      <dependency>          <groupId>com.google.guava</groupId>          <artifactId>guava</artifactId>          <version>15.0</version>      </dependency>      <!--log4j日志框架-->      <dependency>          <groupId>log4j</groupId>          <artifactId>log4j</artifactId>          <version>1.2.17</version>      </dependency>      <dependency>          <groupId>javax.servlet</groupId>          <artifactId>jstl</artifactId>          <version>1.2</version>      </dependency>      <dependency>          <groupId>javax.servlet</groupId>          <artifactId>jsp-api</artifactId>          <version>2.0</version>          <scope>provided</scope>      </dependency>

<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns="http://java.sun.com/xml/ns/javaee"          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"          xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"          version="3.0">     <display-name>mybatis</display-name>     <!--spring容器配置-->     <context-param>         <param-name>contextConfigLocation</param-name>         <param-value>classpath:config/context-config.xml</param-value>     </context-param>     <listener>         <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>     </listener>     <!--mvc配置-->     <servlet>         <servlet-name>mvc</servlet-name>         <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>         <init-param>             <param-name>contextConfigLocation</param-name>             <param-value>classpath:config/dispatcher-config.xml</param-value>         </init-param>         <load-on-startup>1</load-on-startup>     </servlet>     <servlet-mapping>         <servlet-name>mvc</servlet-name>         <url-pattern>/</url-pattern>     </servlet-mapping> </web-app>

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">      <property name="driverClassName" value="${jdbc.mysql.driverClassName}"/>      <property name="url" value="${jdbc.mysql.url}"/>      <property name="username" value="${jdbc.mysql.username}"/>      <property name="password" value="${jdbc.mysql.password}"/>      <property name="maxActive" value="${jdbc.mysql.maxActive}"/>      <property name="maxIdle" value="${jdbc.mysql.maxIdle}"/>      <property name="initialSize" value="${jdbc.mysql.initialSize}"/>      <property name="maxWait" value="${jdbc.mysql.maxWait}"/> </bean> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">      <property name="dataSource" ref="dataSource" /> </bean> <context:component-scan base-package="com.sz.mybatis.framework.service">      <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/> </context:component-scan>   <context:annotation-config /> <tx:annotation-driven /> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean" scope="singleton" >      <property name="dataSource" ref="dataSource" />      <property name="typeAliasesPackage" value="com.sz.mybatis.framework.domain.blog" />      <property name="mapperLocations">           <list>               <value>classpath:com/sz/mybatis/framework/persist/BlogMapper.xml</value>           </list>      </property> </bean> <bean id="sqlSession" factory-bean="sqlSessionFactory" factory-method="openSession" scope="prototype"></bean>

<context:component-scan base-package="com.sz.mybatis.admin.controller">      <!--<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>--> </context:component-scan> <mvc:default-servlet-handler/> <mvc:annotation-driven/> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">      <property name="suffix" value=".jsp"></property>      <property name="prefix" value="/page/"></property>      <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>      <!--<property name="contentType" value="UTF-8"/>--> </bean>

 

来一个博客对象的增删改查先；controller先来，这是概要；

而后是url映射：

servic直接略过，主要关注dao的实现，先来个接口先；

 

实现：

package com.sz.mybatis.framework.service.impl; import com.google.common.collect.ImmutableList; import com.sun.deploy.association.utility.AppConstants; import com.sz.mybatis.framework.domain.Msg; import com.sz.mybatis.framework.domain.PageConfig; import com.sz.mybatis.framework.domain.blog.Blog; import com.sz.mybatis.framework.persist.BlogDao; import com.sz.mybatis.framework.persist.BlogMapper; import com.sz.mybatis.framework.service.BlogService; import com.sz.mybatis.framework.util.SystemConstant; import org.apache.ibatis.session.SqlSession; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import java.util.List; /** * Created with IntelliJ IDEA. * User: cutter.li * Date: 14-2-28 * Time: 下午3:07 * 服务实现类 */ @Service public class BlogServiceBean implements BlogService {     @Autowired     SqlSession session;     private BlogMapper getBlogMapper() {         return session.getMapper(BlogMapper.class);     }     @Override     public Msg list(PageConfig pageConfig) {         if (pageConfig != null) {             BlogMapper blogMapper = getBlogMapper();             List<Blog> blogList= blogMapper.list(pageConfig);             Msg msg=new Msg();             if(blogList!=null)             {                 msg.setCode(SystemConstant.SUCCESS);                 msg.setMessage(SystemConstant.SUCCES_MESSAGE);                 msg.setData(blogList);             }             return msg;         }         return null;     }     @Override     public Blog listSingle(int id) {         if (id > 0) {             BlogMapper blogMapper = getBlogMapper();             Blog blog = blogMapper.selectBlog(id);             return blog;         }         return null;     }     @Override     public void modify(Blog blog) {         getBlogMapper().updateBlog(blog);     }     @Override     public void insert(Blog blog) {         getBlogMapper().insertBlog(blog);     }     @Override     public void remove(int id) {         getBlogMapper().deleteBlog(id);     } }

配置文件: <?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.sz.mybatis.framework.persist.BlogMapper">     <select id="selectBlog" resultType="Blog">     select * from Blog where id = #{id}   </select>     <select id="list" parameterType="com.sz.mybatis.framework.domain.PageConfig" resultType="com.sz.mybatis.framework.domain.blog.Blog">         select * from Blog  order by #{sortField} #{sortOrder}  limit  #{start},#{pageSize}     </select>      <insert id="insertBlog" parameterType="Blog">          insert into Blog (title,contentSummary,contentDetail) values(#{title},#{contentSummary},#{contentDetail})      </insert>     <update id="updateBlog" parameterType="Blog">         update Blog set title=#{title} , contentSummary=#{contentSummary} ,contentDetail=#{contentDetail} where id=#{id}     </update>     <delete id="deleteBlog" parameterType="int">         delete from Blog where id=#{id}     </delete> </mapper>

一个接口方法对应一条配置，经过id对应起来，听说能够在类的注解上面写sql，那会更简单，有空我改为注解的，敬请期待…

来几张效果图先：

 

 

两个图对比标识完成了分页的操做；

两个图对比表示实现了增长的功能；

 

两个图对比表示实现了编辑的功能；

 

最后标识实现了删除的功能；

 

到这里crud的程序算完成了，mybatis成功的入门了…

 

对了，附上源码...