SSM框架集成

SSM

1 介绍

SSM框架是指Spring + Spring MVC + MyBatis的组合，是一种常用的Java Web开发框架。这三个框架分别提供了不同的功能：

• Spring（Spring Framework）： 提供了IoC（控制反转）和AOP（面向切面编程）等功能，用于管理Java应用中的对象和组件，并提供了事务管理等企业级特性。

• Spring MVC： 是Spring框架的一部分，用于构建Web应用程序的MVC框架，提供了基于Java的配置、灵活的URL映射、强大的数据绑定、表单处理和验证等功能。

• MyBatis： 是一个持久层框架，用于将Java对象与数据库中的记录进行映射，提供了简单的SQL操作和结果映射。

SSM框架整合这三个框架，可以使得开发者在开发Java Web应用时更加方便和高效。典型的SSM框架的工作流程如下：

1. 请求到达前端控制器（DispatcherServlet）： 所有的请求都会先到达前端控制器，即DispatcherServlet。

2. DispatcherServlet分发请求： DispatcherServlet根据请求的URL，使用Handler Mapping找到对应的Controller。

3. Controller处理请求： Controller处理请求，可以调用Service层的方法，Service层包含了业务逻辑。

4. Service层处理业务逻辑： Service层处理业务逻辑，可能会调用DAO层的方法来访问数据库。

5. DAO层访问数据库： DAO层使用MyBatis等持久化框架与数据库进行交互。

6. 返回结果给前端控制器： 数据库返回结果，Service层将结果传递给Controller。

7. 前端控制器选择视图并返回： Controller选择合适的视图（通常是JSP页面），并将结果传递给前端控制器。

8. 前端控制器返回响应： 前端控制器将视图渲染成HTML等内容，并返回给客户端。

2 集成步骤

目录结构

配置 web.xml

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    
    <filter>
        <filter-name>encodingfilter-name>
        <filter-class>com.kdx.filter.CharSetEncodingfilter-class>
    filter>

    <filter-mapping>
        <filter-name>encodingfilter-name>
        <url-pattern>*.actionurl-pattern>
    filter-mapping>

    
    <context-param>
        <param-name>contextConfigLocationparam-name>
        <param-value>classpath:applicationContext-*.xmlparam-value>
    context-param>
    
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListenerlistener-class>
    listener>

    
    <servlet>
        <servlet-name>springmvcservlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServletservlet-class>
        <init-param>
            <param-name>contextConfigLocationparam-name>
            <param-value>classpath:springmvc.xmlparam-value>
        init-param>
    servlet>
    
    <servlet-mapping>
        <servlet-name>springmvcservlet-name>
        <url-pattern>*.actionurl-pattern>
    servlet-mapping>
web-app>

配置 jdbc.properties

若 mysql 为8.x版本则配置如下

jdbcs.driver=com.mysql.cj.jdbc.Driver

若 mysql 为8.x版本之前则配置如下

jdbcs.driver=com.mysql.jdbc.Driver

jdbcs.driver=com.mysql.cj.jdbc.Driver 
jdbcs.url=jdbc:mysql:///mybatis
jdbcs.uname=root
jdbcs.pwd=kdx010908

配置 SqlMapConfig.xml

DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <plugins>
        <plugin interceptor="com.github.pagehelper.PageInterceptor">
        plugin>
    plugins>
configuration>

配置 applicationContext-dao.xml

<beans xmlns="http://www.springframework.org/schema/beans"
	   xmlns:context="http://www.springframework.org/schema/context"
	   xmlns:mvc="http://www.springframework.org/schema/mvc" 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" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
	   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
	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
	http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc.xsd">
	
	<context:property-placeholder location="classpath:jdbc.properties">context:property-placeholder>
	
	<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
		  <property name="driverClassName" value="${jdbcs.driver}">property>
		  <property name="url" value="${jdbcs.url}">property>
		  <property name="username" value="${jdbcs.uname}">property>
		  <property name="password" value="${jdbcs.pwd}">property>
	bean>

	
	<bean class="org.mybatis.spring.SqlSessionFactoryBean">
		<property name="dataSource" ref="dataSource">property>
		<property name="configLocation" value="classpath:SqlMapConfig.xml">property>
		<property name="typeAliasesPackage" value="com.kdx.entity">property>
	bean>

	
	<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
		<property name="basePackage" value="com.kdx.mapper">property>
	bean>
beans>

配置 applicationContext-service.xml

<beans xmlns="http://www.springframework.org/schema/beans"
	   xmlns:context="http://www.springframework.org/schema/context"
	   xmlns:mvc="http://www.springframework.org/schema/mvc" 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.xsd
	 http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.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
	http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd">
	
	
	<context:component-scan base-package="com.kdx.service">context:component-scan>
beans>

配置 log4j.properties

# Global logging configuration
log4j.rootLogger=DEBUG, stdout
# MyBatis logging configuration...
log4j.logger.org.mybatis.example.BlogMapper=TRACE
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

编写解决中文乱码的过滤器

public class CharSetEncoding implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        request.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("utf-8");
        chain.doFilter(request,response);
    }

    @Override
    public void destroy() {

    }
}

编写实体类

public class Items {
    private Integer id;

    private String name;

    private Float price;

    private String pic;

    private String detail;

    private Date createtime;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

    public Float getPrice() {
        return price;
    }

    public void setPrice(Float price) {
        this.price = price;
    }

    public String getPic() {
        return pic;
    }

    public void setPic(String pic) {
        this.pic = pic == null ? null : pic.trim();
    }

    public Date getCreatetime() {
        return createtime;
    }

    public void setCreatetime(Date createtime) {
        this.createtime = createtime;
    }

    public String getDetail() {
        return detail;
    }

    public void setDetail(String detail) {
        this.detail = detail == null ? null : detail.trim();
    }
}

编写 ItemsMapper 接口

public interface ItemsMapper {

    //查询全部的商品
    public List<Items> findAll();
}

编写映射 ItemsMapper.xml

DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.easthome.mapper.ItemsMapper">

    <select id="findAll" resultType="com.easthome.entity.Items">
        select * from items
    select>
mapper>

编写 ItemsService 接口

public interface ItemsService {

    List<Items> queryAll();
}

编写 ItemsServiceImpl 实现 ItemsService 接口

@Service
public class ItemsServiceImpl implements ItemsService {

    @Autowired
    private ItemsMapper itemsMapper;

    @Override
    public List<Items> queryAll() {
        List<Items> itemsList = itemsMapper.findAll();
        return itemsList;
    } 
}

编写 ItemsController

第一种写法：

@Controller
public class ItemsController {

    @Autowired
    private ItemsService itemsService;

    @RequestMapping("/list")
    public ModelAndView list(){
        ModelAndView mav = new ModelAndView();
        List<Items> itemsList = itemsService.queryAll();
        mav.addObject("itemsList",itemsList);
        mav.setViewName("list");
        return mav;
    }
}

第二种写法：

	@RequestMapping("/list")
    public List<Items> list(){
        //自动封装一个集合数据  itemsList 自动去视图解析器下面找  itemsList.jsp页面
        return itemsService.queryAll();
    }

第三种写法：

    @RequestMapping("/list")
    public void list(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        List<Items> itemsList = itemsService.queryAll();
        request.setAttribute("itemsList",itemsList);
        request.getRequestDispatcher("/WEB-INF/jsps/list.jsp").forward(request,response);
    }

第四种写法：

    @RequestMapping("/list")
    public void list(Map<String,Object> map) {
        //自动封装一个集合数据  itemsList 自动去视图解析器下面找  itemsList.jsp页面
        map.put("itemsList",itemsService.queryAll());
    }

最后编写前端页面

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
    <title>开发视图title>
head>
<body>
<table width="600px" border="1" align="center">
    <tr>
        <td>商品序号td>
        <td>商品名称td>
        <td>商品价格td>
        <td>商品简介td>
        <td>操作td>
    tr>
    <c:forEach items="${requestScope.itemsList}" var="items">

        <tr>
            <td>${items.id}td>
            <td>${items.name}td>
            <td>${items.price}td>
            <td>${items.detail}td>
            <td>
                <a href="${pageContext.request.contextPath}/delItem.action?ids=${items.id}">删除a>
            td>
        tr>
    c:forEach>
table>
body>
html>

部署运行：