• SSM 框架集成


    1.SSM是什么?

    SSM是指目前最主流的项目架构的三大框架:
      SpringMVC : spring的 Web层框架,是spring的一个模块
      Spring :容器框架
      MyBatis :持久层框架

     

    2.spring与mybatis集成示例

      我们集成mybatis和spring,主要是为了让mybatis用spring的事务管理

      2.1 相关导入jar包

        Spring依赖包:

      

        mybatis依赖包:

       

        MyBatis和Spring框架集成的桥梁包:

        Spring自己并没有集成MyBatis框架,而是有MyBatis自己来集成,所以还需要Spring框架集成的桥梁包

       

        

        数据库驱动包和连接池:

       

       

        Mybatis支持的日志包log4j:

        

      2.2 项目整体结构

      

      2.3 Mapper层

    package com.gjs.ssm.mapper;
    
    import java.util.List;
    import com.gjs.ssm.pojo.User;
    
    public interface UserMapper {
        
        public    int insert(User user);
        
        public User selectByPrimaryKey(Integer id);
        
        public List<User> selectList();
        
        public int delteByPrimaryKey(Integer id);
    }

      Mapper.xml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.gjs.ssm.mapper.UserMapper">
        
        <insert id="insert" parameterType="com.gjs.ssm.pojo.User">
            insert into user (name,password,age)values(#{name},#{password},#{age})
        </insert>
        
        <select id="selectByPrimaryKey" parameterType="Integer" resultType="com.gjs.ssm.pojo.User">
            select * from user where id = #{id}
        </select>
        
        <select id="selectList"  resultType="com.gjs.ssm.pojo.User">
            select * from user
        </select>
          
          <delete id="delteByPrimaryKey" parameterType="int">
              delete from user where id = #{id}
          </delete>
          
    </mapper>

      2.4 Service层

    package com.gjs.ssm.service.impl;
    
    import java.util.List;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    
    import com.gjs.ssm.mapper.UserMapper;
    import com.gjs.ssm.pojo.User;
    import com.gjs.ssm.service.UserService;
    
    @Service
    public class UserSerivceImpl implements UserService{
        @Autowired
        UserMapper userMapper;
        
        @Override
        public int inset(User user) {
            return userMapper.insert(user);
        }
    
        @Override
        public User selectByPrimaryKey(Integer id) {
            return userMapper.selectByPrimaryKey(id);
        }
    
        @Override
        public List<User> selectList() {
            return userMapper.selectList();
        }
    
        @Override
        public int delteByPrimaryKey(Integer id) {
            return userMapper.delteByPrimaryKey(id);
        }
    
    }

      2.5层与层之间(Mapper和Service)spring对象的创建和依赖关系的维护(A)

      之前我们Mapper对象的创建是通过sqlSession对象创建的,sqlSession对象又是SqlSessionFactory对象创建出来的,而SqlSessionFactory对象是通过读取配置文件中的相关配置创建的。
      所谓的spring与mybatis集成,说白了就是把这些对象的创建都交给spring来处理。那怎么让spring自己创建这些对象呢?
      spring-mybatis桥梁包中提供的org.mybatis.spring.SqlSessionFactoryBean类可以创建SqlSessionFactory对象,org.mybatis.spring.mapper.MapperScannerConfigurer类可以用来创建 Mapper接口的代理对象。所以只要在spring中配置这两个对象并注入依赖即可。具体配置如下:

    spring.xml:

    <?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:p="http://www.springframework.org/schema/p"
        xmlns:context="http://www.springframework.org/schema/context"
        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.xsd
            http://www.springframework.org/schema/context
            http://www.springframework.org/schema/context/spring-context.xsd
            http://www.springframework.org/schema/aop
            http://www.springframework.org/schema/aop/spring-aop.xsd
            http://www.springframework.org/schema/tx
            http://www.springframework.org/schema/tx/spring-tx.xsd
            ">
            
        <!-- 开启注解包扫描 -->
        <context:component-scan base-package="com.gjs.ssm"/>
        
        <!-- 读取db.properties 配置文件 -->
        <context:property-placeholder location="classpath:db.properties"/>
        
        
        <!-- 配置druid连接池 -->
        <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
            <property name="driverClassName" value="${jdbc.driverClassName}"/>
            <property name="url" value="${jdbc.url}"/>
            <property name="username" value="${jdbc.username}"/>
            <property name="password" value="${jdbc.password}"/>
            <property name="maxActive" value="${jdbc.maxActive}"/>
        </bean>
        
        <!-- 配置SqlSessionFactoryBean对象 -->
        <bean name="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
            <!-- 注入数据源 -->
            <property name="dataSource" ref="dataSource"/>
            
            <!-- 配置映射文件 -->
            <property name="mapperLocations">
                <array>
                    <value>classpath:com/gjs/ssm/mapper/*Mapper.xml</value>
                </array>
            </property>
    
            <!-- 配置包扫描的别名 -->
            <property name="typeAliasesPackage" value="com.gjs.ssm.pojo"/>
        
            <!-- 
            如果需要读取mybatis框架的配置文件mybat-config.xml可使用:
            <property name="configLocation" value="classpath:mybatis-config.xml"/>
            不过一般不需要
             -->
             
        </bean>
        
        <!-- SqlSession对象的创建只需通过sqlSessionFactory对象调用openSession()方法即可,spring会自动创建 -->
        
        <!-- 使用包扫描批量创建 Mapper接口对应的代理对象 -->
        <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
            <!-- 配置包扫描创建代理对象的位置 -->
            <property name="basePackage" value="com.gjs.ssm.mapper"/>
            
            <!-- 注入sqlSessionFactory bean的名称 -->
            <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        </bean>
        
        
        
        <!-- 配置事务管理器 -->
        <bean id="txManager"  class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
            <!-- 注入数据源 -->
            <property name="dataSource" ref="dataSource"/>
        </bean>
        
        
        <!-- 配置事务通知 -->
        
        <tx:advice id="txAdvice" transaction-manager="txManager">
            <tx:attributes>
                <!-- DQL -->
                <tx:method name="select*" read-only="true" isolation="REPEATABLE_READ" propagation="REQUIRED"/>
                <tx:method name="get*" read-only="true" isolation="REPEATABLE_READ" propagation="REQUIRED"/>
                <tx:method name="find*" read-only="true" isolation="REPEATABLE_READ" propagation="REQUIRED"/>
                <tx:method name="query*" read-only="true" isolation="REPEATABLE_READ" propagation="REQUIRED"/>
                <!-- 非DQL  -->
                <tx:method name="*" read-only="false" isolation="REPEATABLE_READ" propagation="REQUIRED"/>        </tx:attributes>
        </tx:advice>
        
        
        
        <!-- 使用AOP将事务切入到service层 -->
        <aop:config >
            <!-- 切入点 -->
            <aop:pointcut expression="execution(* com.gjs.ssm.service..*.*(..))" id="pt"/>
            
            <!-- 切面 = 切入点+通知-->
            <aop:advisor advice-ref="txAdvice" pointcut-ref="pt"/>
            
            <!-- Spring 负责织入 -->
        </aop:config>
    
    </beans>

      下面这段代码是其中的关键

    <!-- 配置SqlSessionFactoryBean对象 -->
        <bean name="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
            <!-- 注入数据源 -->
            <property name="dataSource" ref="dataSource"/>
            
            <!-- 配置映射文件 -->
            <property name="mapperLocations">
                <array>
                    <value>classpath:com/gjs/ssm/mapper/*Mapper.xml</value>
                </array>
            </property>
    
            <!-- 配置包扫描的别名 -->
            <property name="typeAliasesPackage" value="com.gjs.ssm.pojo"/>
        
            <!-- 
            如果需要读取mybatis框架的配置文件mybat-config.xml可使用:
            <property name="configLocation" value="classpath:mybatis-config.xml"/>
            不过一般不需要
             -->
             
        </bean>
        
        <!-- SqlSession对象的创建只需通过sqlSessionFactory对象调用openSession()方法即可,spring会自动创建 -->
        
        <!-- 使用包扫描批量创建 Mapper接口对应的代理对象 -->
        <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
            <!-- 配置包扫描创建代理对象的位置 -->
            <property name="basePackage" value="com.gjs.ssm.mapper"/>
            
            <!-- 注入sqlSessionFactory bean的名称 -->
            <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        </bean>

      2. 5 测试代码

    package com.gjs.ssm.test;
    
    import java.util.List;
    
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.test.context.ContextConfiguration;
    import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
    
    import com.gjs.ssm.pojo.User;
    import com.gjs.ssm.service.UserService;
    
    
    @RunWith(SpringJUnit4ClassRunner.class)
    @ContextConfiguration("classpath:spring.xml")
    public class UserSerivceImplTest {
    
        @Autowired
        private UserService userService;
        
        @Test
        public void testInset() {
            User user = new User(null, "张三", "123", 30);
            int row = userService.inset(user);
            System.out.println(row);
        }
        
        @Test
        public void testSelectByPrimaryKey() {
            User user = userService.selectByPrimaryKey(3);
            System.out.println(user);
        }
    
        @Test
        public void testSelectList() {
            List<User> selectList = userService.selectList();
            System.out.println(selectList);
        }
    
        @Test
        public void testDelteByPrimaryKey() {
            int row = userService.delteByPrimaryKey(3);
            System.out.println(row);
        }
    
    }

    3.SpringMVC的集成

      3.1 导入相关jar包  

      SpringMVC依赖包:

      

      Jstl标签库依赖包:

      

      3.2 项目整体结构

       

      3.3 springmvc.xml配置文件

    <?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:p="http://www.springframework.org/schema/p"
        xmlns:mvc="http://www.springframework.org/schema/mvc"
        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.xsd
            http://www.springframework.org/schema/mvc
            http://www.springframework.org/schema/mvc/spring-mvc.xsd
            ">
        <!-- 开启springMVC注解驱动 -->
        <mvc:annotation-driven/>
            
    </beans>

      3.4 编写控制器

    package com.gjs.ssm.controller;
    
    import java.util.List;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.Model;
    import org.springframework.web.bind.annotation.RequestMapping;
    
    import com.gjs.ssm.pojo.User;
    import com.gjs.ssm.service.UserService;
    
    @Controller
    @RequestMapping("/user")
    public class UserController {
         
        @Autowired
        private UserService userService;
        
        @RequestMapping("/list")
        public String list(Model model) {
             
            List<User> users = userService.selectList();
            model.addAttribute("users", users);
             
            return "/WEB-INF/view/user_list.jsp";
        }
    }

      3.5 在web.xml配置SpringMVC的前端控制器(关键)

      web.xml是整个web项目的入口,其他配置文件都需要通过web.xml直接或间接读取。所以springMVC和spring集成的关键就在于在web.xml中配置读取spring和springMVC的配置文件。

    <?xml version="1.0" encoding="UTF-8"?>
    <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" version="3.1">
      <display-name>SSM集成</display-name>
      <welcome-file-list>
        <welcome-file>index.html</welcome-file>
        <welcome-file>index.htm</welcome-file>
        <welcome-file>index.jsp</welcome-file>
        <welcome-file>default.html</welcome-file>
        <welcome-file>default.htm</welcome-file>
        <welcome-file>default.jsp</welcome-file>
      </welcome-file-list>
      
      <!-- 配置字符编码过滤器 -->
      <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>
      
      <!-- 配置前端控制器 (分发器)-->
      <servlet>
          <servlet-name>MVC</servlet-name>
          <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
          
          <init-param>
              <!-- 读取配置文件 用通配符 *可以读取多个有相同前缀和后缀的文件-->
              <param-name>contextConfigLocation</param-name>
              <param-value>classpath:spring*.xml</param-value>
          </init-param>
          <load-on-startup>1</load-on-startup>
      </servlet>
      <servlet-mapping>
          <servlet-name>MVC</servlet-name>
          <url-pattern>*.do</url-pattern>
      </servlet-mapping>
    </web-app>

      3.6 编写jsp页面测试

    <%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    <!-- 引入jstl标签库  -->
    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
    <!DOCTYPE html>
    <html>
        <head>
            <meta charset="UTF-8">
            <title>Insert title here</title>
        </head>
    <body>
        <h3>用户列表</h3>
     
        <table border="1" style=" 500px;" cellspacing="0">
            <tr>
                <th>id</th>
                <th>名称</th>
                <th>密码</th>
                <th>年龄</th>
            </tr>
     
     
        <c:forEach items="${users}" var="user">
            <tr>
                <td>${user.id}</td>
                <td>${user.name}</td>
                <td>${user.password}</td>
                <td>${user.age}</td>
            </tr>
        </c:forEach>
        </table>
    
    </body>
    </html>
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  • 原文地址:https://www.cnblogs.com/gaojinshun/p/11227900.html
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