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SSM 框架集成

程序员文章站 2022-05-03 22:21:44
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myba ......

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:

  SSM 框架集成

    mybatis依赖包:

   SSM 框架集成

    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

   SSM 框架集成

    

    数据库驱动包和连接池:

   SSM 框架集成

   SSM 框架集成

    mybatis支持的日志包log4j:

    SSM 框架集成

  2.2 项目整体结构

  SSM 框架集成

  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:

  SSM 框架集成

  jstl标签库依赖包:

  SSM 框架集成

  3.2 项目整体结构

   SSM 框架集成

  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="width: 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>