SSM入門（案例）

版權聲明：本文爲博主原創文章，未經博主允許不得轉載。 https://blog.csdn.net/BlueSkyInMyMind/article/details/79422093

一概述

SSM
spring web mvc(表現層) + spring + mybatis（持久層）
springmvc是spring的一部分，不需要整合包

二實例

目標：將商品信息顯示到頁面

1.創建一個web工程

2.導入相關jar包

3.創建配置文件

• mybatis配置
  
  • sqlMapConfig.xml(空配置，需要一個根標籤)

<?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>

 · 映射文件逆向工程生成

• spring配置
  -applicationContext-dao.xml dao層配置

    <?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-4.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd">

    <!-- 加載配置文件 -->
    <context:property-placeholder location="classpath:db.properties" />
    <!-- 數據庫連接池 -->
    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
        destroy-method="close">
        <property name="driverClassName" value="${jdbc.driver}" />
        <property name="url" value="${jdbc.url}" />
        <property name="username" value="${jdbc.username}" />
        <property name="password" value="${jdbc.password}" />
        <property name="maxActive" value="10" />
        <property name="maxIdle" value="5" />
    </bean>
    <!-- mapper配置 -->
    <!-- 讓spring管理sqlsessionfactory 使用mybatis和spring整合包中的 -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <!-- 數據庫連接池 -->
        <property name="dataSource" ref="dataSource" />
        <!-- 加載mybatis的全局配置文件 -->
        <property name="configLocation" value="classpath:mybatis/SqlMapConfig.xml" />
    </bean>
    <!-- 配置Mapper掃描器 -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.blueSky.mapper" />
    </bean>

</beans>

-applicationContext-service.xml  service層配置

<?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-4.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd">

<context:component-scan base-package="com.blueSky.service"/>

</beans>

-applicationContext-transacation.xml 事務配置（service層方法加事務）

<?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-4.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd">
    <!-- 事務管理器 -->
    <bean id="transactionManager"
        class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <!-- 數據源 -->
        <property name="dataSource" ref="dataSource" />
    </bean>
    <!-- 通知 -->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <!-- 傳播行爲 -->
            <tx:method name="save*" propagation="REQUIRED" />  <!-- 若無事務，開啓事務  -->
            <tx:method name="insert*" propagation="REQUIRED" />
            <tx:method name="delete*" propagation="REQUIRED" />
            <tx:method name="update*" propagation="REQUIRED" />
            <tx:method name="find*" propagation="SUPPORTS" read-only="true" /> <!-- 當前事務，不開啓事務 -->
            <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.blueSky.service.*.*(..))" />
    </aop:config>
</beans>

• springmvc springmvc配置

<?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-4.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
        http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">

    <!-- 掃描帶Controller註解的類 -->
    <context:component-scan base-package="com.blueSky.controller" />
    <!-- 加載註解驅動 -->
    <mvc:annotation-driven />
    <!-- 視圖解析器 -->
    <bean
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="viewClass"
            value="org.springframework.web.servlet.view.JstlView" />
        <!-- jsp前綴 -->
        <property name="prefix" value="/WEB-INF/jsp/" />
        <!-- jsp後綴 -->
        <property name="suffix" value=".jsp" />
    </bean>
</beans>

• web.xml配置
  -配置springmvc前端控制器（DispatchServlet）
  -加載spring容器配置

<?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"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
    id="WebApp_ID" version="3.0">
    <display-name>SSM</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>
    <!-- 加載spring容器 -->
    <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>

    <servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring/springmvc.xml</param-value>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>*.action</url-pattern>
    </servlet-mapping>
</web-app>

4.編寫代碼

查詢從後向前，先想SQL語句。
- dao層（mapper目錄）
mybatis逆向工程生成代碼，mapper接口和mapper映射文件
- service層
創建接口，實現類調用dao層方法

package com.blueSky.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.blueSky.mapper.ItemsMapper;
import com.blueSky.pojo.Items;

public interface ItemsService {

    public List<Items> getItemsList();
}

package com.blueSky.service.impl;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.blueSky.mapper.ItemsMapper;
import com.blueSky.pojo.Items;
import com.blueSky.pojo.ItemsExample;
import com.blueSky.service.ItemsService;
@Service
public class ItemServiceImpl implements ItemsService {
    @Autowired
    private ItemsMapper itemsMapper;

    @Override
    public List<Items> getItemsList() {
        ItemsExample itemsExample = new ItemsExample();
        List<Items> list = itemsMapper.selectByExampleWithBLOBs(itemsExample);
        return list;
    }
}

• view層
  調用service層方法獲得參數

package com.blueSky.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

import com.blueSky.pojo.Items;
import com.blueSky.service.ItemsService;
@Controller
public class ItemsController {

    @Autowired
    private ItemsService itemsService;

    /*1.編寫handler方法（配置註解resultmapping）
     *2.調用service層方法獲取數據
     *3.創建modelandview對象
     *4.將數據存入request域，modelandview.addObject，設置對象名
     *5.設置視圖解析器路徑
     *6.返回ModelAndView
    */
    @RequestMapping("itemList.action")
    public ModelAndView getItemsList(){
        List<Items> itemsList = itemsService.getItemsList();
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.addObject("itemList", itemsList);
        modelAndView.setViewName("itemList");
        return modelAndView;
    }
}