介绍:本文中示范搭建一个ssm环境的框架:使用流程就是客户端通过http请求访问指定的接口,然后由服务器接受到请求处理完成后将结果返回。
本项目请求流程细节介绍:由客户端请求到指定的接口,这个接口是个jsp的页面,在jsp页面中会自动请求jsp中指定的接口,请求到达comcat服务器后由spring mvc提供的DispatchServlet类进行接受,然后将请求交给HandierMapping接口的实现类去解析当前请求的所有参数,再交给HandlerAdaper接口的实现类去将所有参数和对象(如:Request, Response)封装后,再调用具体的后台逻辑中的controller接口。当controller接口执行完毕后会将结果返回给调用者(因为这里直接请求后台的是jsp所以会返回给jsp),然后由jsp将结果进行美化后展示给浏览器展现出来。本项目中前端展示用jsp来展示的,其实也可以用前后分离的方式,将后端的处理结果直接响应给前端,然后前端接受到后直接自己专门用专业的前端技术处理结果,然后展示给客户端即可。
*jsp处理简介:jsp其实也就是servlet,因为tomcat中有一个servlet会将jsp文件读取过来然后自动生成对应的java代码,其中的标签就用字符串描述以IO流方式输出打印到浏览器。
上代码:
数据库:
1.web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app version="3.0" 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"> <!-- 配置上下文参数:就是配置spring的xml路径 --> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext.xml</param-value> </context-param> <!-- 配置监听器 --> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <!-- 配置spring前端控制器,用于接受所有的http请求的一个servlet --> <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:springmvc.xml</param-value> </init-param> <!-- 添加自启动,在加载这个在服务器刚开始加载这个文件的时候就将此Servlet实例化了,如果不加,则等到真正调用 时才会实例化 --> <load-on-startup>1</load-on-startup> </servlet> <!-- 配置访问名叫springmvc的这个servlet时:除过一点jsp结尾的请求会被过滤外,其他请求皆会接受 --> <servlet-mapping> <servlet-name>springmvc</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <!-- 配置字符编码过滤器:当前只对post请求有效,其他请求没试过,get请求不行 --> <filter> <filter-name>encoding</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> <!-- 配置将哪些路径请求编码,这里配置的是所有 --> <filter-mapping> <filter-name>encoding</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <!-- 修改Tomcat默认首页的jsp文件,此处配置了aa.jsp,那么如果直接访问http://localhost:8080/ssm/单独只有斜杠 的话就会直接走首页的jsp,此处已经将默认的index.jsp换为aa.jsp --> <welcome-file-list> <welcome-file>aa.jsp</welcome-file> </welcome-file-list> </web-app>
2.applicationContext.xml
<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd" default-autowire="byName"> <!-- 扫描注解:但凡是此包下的类都会扫描,然后将其加载到spring的容器中,此时启动完成后spring的容器中就有此对象了 --> <context:component-scan base-package="com.mr.li.service.impl"></context:component-scan> <!-- 加载属性文件 --> <context:property-placeholder location="classpath:db.properties"/> <!-- 配置读取数据源 --> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="${jdbc.driver}"></property> <property name="url" value="${jdbc.url}"></property> <property name="username" value="${jdbc.username}"></property> <property name="password" value="${jdbc.password}"></property> </bean> <!-- SqlSessionFactory --> <bean id="factory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource"></property> <property name="typeAliasesPackage" value="com.mr.li.pojo"></property> </bean> <!-- 扫描器 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com.mr.li.mapper"></property> <property name="sqlSessionFactoryBeanName" value="factory"></property> </bean> <!-- 事务管理器 --> <bean id="txManage" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource"></property> </bean> <!-- 声明式事务 --> <tx:advice id="txAdvice" transaction-manager="txManage"> <tx:attributes> <tx:method name="ins*"/> <tx:method name="del*"/> <tx:method name="upd*"/> <tx:method name="*" read-only="true"/> </tx:attributes> </tx:advice> <!-- 配置aop --> <aop:config> <aop:pointcut expression="execution(* com.mr.li.service.impl.*.*(..))" id="mypoint"/> <aop:advisor advice-ref="txAdvice" pointcut-ref="mypoint"/> </aop:config> </beans>
3.db.properties:数据库参数properties文件
jdbc.driver=com.mysql.jdbc.Driver jdbc.url = jdbc:mysql://localhost:3306/test jdbc.username = root jdbc.password = 123456
4.springmvc.xml
<?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:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" 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/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd"> <!-- 扫描直接,只扫描controller包 --> <context:component-scan base-package="com.mr.li.controller"></context:component-scan> <!-- 注解驱动,注册HandlerMapping和HandlerAdapter --> <mvc:annotation-driven></mvc:annotation-driven> <!-- 设置静态资源 --> <mvc:resources location="/js/" mapping="/js/**"></mvc:resources> <mvc:resources location="/css/" mapping="/css/**"></mvc:resources> <mvc:resources location="/images/" mapping="/images/**"></mvc:resources> <!-- 视图解析器 --> <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/"></property> <property name="suffix" value=".jsp"></property> </bean> </beans>
5.MenuMapper.java:相当于Dao层,java映射类(映射到mapper.xml中,而mapper.xml映射在spring的xml就是applicationContext.xml中有调用,调用处:id="factory")
package com.mr.li.mapper; /** * 相当于dao的Service * @author Administrator * */ import java.util.List; import com.mr.li.pojo.Menu; public interface MenuMapper { /** * 根据pid获得菜单对象 * @param pid * @return */ List<Menu> selectByPid(int pid); }
6.MenuMapper.xml:映射xml
<?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.mr.li.mapper.MenuMapper"> <resultMap type="menu" id="mymap"> <id property="id" column="id"/> <collection property="children" select="com.mr.li.mapper.MenuMapper.selectByPid" column="id"></collection> </resultMap> <select id="selectByPid" parameterType="int" resultMap="mymap"> select * from menu where pid=#{0} </select> </mapper>
7.MenuController.java:客户端要访问的哪个接口
package com.mr.li.controller; import java.util.List; import javax.annotation.Resource; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.ResponseBody; import com.mr.li.pojo.Menu; import com.mr.li.service.MenuService; @Controller public class MenuController { @Resource private MenuService menuServiceImpl; @RequestMapping("show") @ResponseBody public List<Menu> show(){ return menuServiceImpl.show(); } @RequestMapping("show1") @ResponseBody public String show1(){ return "hello world"; } }
8.Menu.java 实体类
package com.mr.li.pojo; import java.util.List; public class Menu { private int id; private String name; private int pid; private List<Menu> children; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getPid() { return pid; } public void setPid(int pid) { this.pid = pid; } public List<Menu> getChildren() { return children; } public void setChildren(List<Menu> children) { this.children = children; } }
9.service
package com.mr.li.service; import java.util.List; import com.mr.li.pojo.Menu; public interface MenuService { /** * 查看所有菜单 * @return */ List<Menu> show(); }
10.serviceImpl
package com.mr.li.service.impl; import java.util.List; import javax.annotation.Resource; import org.springframework.stereotype.Service; import com.mr.li.mapper.MenuMapper; import com.mr.li.pojo.Menu; import com.mr.li.service.MenuService; @Service public class MenuServiceImpl implements MenuService{ @Resource private MenuMapper menuMapper; @Override public List<Menu> show() { return menuMapper.selectByPid(0); } }
11.默认请求页面:aa.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> <script type="text/javascript" src="js/jquery-1.7.2.js"></script> <script type="text/javascript"> $(function(){ $.post("show",function(data){ var result =""; for(var i=0;i<data.length;i++){ result+="<dl>"; result+="<dt style=‘cursor:pointer‘>"+data[i].name+"</dt>"; for(var j=0;j<data[i].children.length;j++){ result+="<dd>"+data[i].children[j].name+"</dd>"; } result+="</dl>"; } $("body").html(result); }); //对所有父菜单添加点击事件 //live("事件名,多个事件使用空格分割",function(){}) $("dt").live("click",function(){ //slow normal fast 数值 $(this).siblings().slideToggle(1000); }); }) </script> </head> <body> </body> </html>
12.jquery-1.7.2:贴不了,自己导入,这不是重点:只要前端收到请求就好
项目页面分布:
请求的url:http://localhost:8080/ssm/aa.jsp
原文地址:https://www.cnblogs.com/li-yan-long/p/10740813.html