Spring　MVC框架搭建及运行流程

小灰灰 2022-08-22 01:25 234阅读 0赞

一、搭建Spring ＭＶＣ框架步骤

1、创建Dynamic Web Project

2、导入spring和springmvc所需要的文件（jar包）

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3、配置web.xml文件

<context-param>
 <param-name>contextConfigLocation</param-name>
 <param-value>/WEB-INF/classes/applicationContext-*.xml</param-value>
 </context-param>
 <pre name="code" class="html"> 
 <listener>
 <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
 </listener>

<servlet>
 <servlet-name>mvc</servlet-name>
 <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
 <init-param>
 <param-name>contextConfigLocation</param-name>
 <param-value>/WEB-INF/classes/applicationContext-servlet.xml</param-value>
 </init-param>
 <load-on-startup>2</load-on-startup>
 </servlet>
 <pre name="code" class="html"> <servlet-mapping>
 <servlet-name>mvc</servlet-name>
 <url-pattern>*.htm</url-pattern>
 </servlet-mapping>

<welcome-file-list>
 
 <welcome-file>/view/default.jsp</welcome-file>
 </welcome-file-list>
 
 
 <error-page>
 <error-code>404</error-code>
 <location>/home/exception.htm?errorCode=404</location>
 </error-page>

3.1 监听spring上下文容器

3.2 加载spring的xml文件到spring的上下文容器(spring-context.xml)

3.3 配置spring MVC的DispatcherServlet

3.4 加载spring MVC的xml到spring的上下文容器(springMVC-context.xml)

3.5 配置DispatcherServlet所需要拦截的 url（固定了HTTP的格式 如\*.do）

4、配置spring的xml文件\----主要配置链接数据库等信息application-datasource.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:jee="http://www.springframework.org/schema/jee"
 	xmlns:aop="http://www.springframework.org/schema/aop"
 	xmlns:tx="http://www.springframework.org/schema/tx"
 	xmlns:context="http://www.springframework.org/schema/context"
 	xmlns:ehcache="http://ehcache-spring-annotations.googlecode.com/svn/schema/ehcache-spring"
 	xsi:schemaLocation="http://www.springframework.org/schema/beans
 http://www.springframework.org/schema/beans/spring-beans-3.0.xsd 
 						http://www.springframework.org/schema/jee 
 						http://www.springframework.org/schema/jee/spring-jee-3.0.xsd
 						http://www.springframework.org/schema/aop
 						http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
 						http://www.springframework.org/schema/tx
 						http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
 						http://www.springframework.org/schema/context 
 					http://www.springframework.org/schema/context/spring-context-3.0.xsd
 					http://ehcache-spring-annotations.googlecode.com/svn/schema/ehcache-spring 
 						http://ehcache-spring-annotations.googlecode.com/svn/schema/ehcache-spring/ehcache-spring-1.1.xsd">
 
 	 					
 <context:property-placeholder location="classpath:jdbc.properties"/>
 
 
 <bean id="initdataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
 		 <property name="url" value="${jdbc.url}"/>
 	<property name="username" value="admin"/>
 	<property name="password" value="123456"/> 
 			<property name="driverClassName" value="${jdbc.driverClassName}"/>
 </bean>
 
 
 
 
 <bean id="realDataSource" class="org.apache.commons.dbcp.BasicDataSource">
 	 <property name="url" value="${jdbc.url}"/>
 		<property name="driverClassName" value="${jdbc.driverClassName}"/>
 		<property name="initialSize" value="8"/>
 		<property name="maxActive" value="20"/>
 		<property name="maxIdle" value="20"/>
 		<property name="minIdle" value="5"/>
 		<property name="maxWait" value="30000"/>
 		<property name="removeAbandonedTimeout" value="20"/>
 		<property name="removeAbandoned" value="true"/>
 		<property name="testWhileIdle" value="true"/> 
 		<property name="testOnBorrow" value="false"/> 
 		<property name="testOnReturn" value="false"/> 
 		<property name="validationQuery" value="select sysdate from dual"/> 
 		<property name="validationQueryTimeout" value="1"/> 
 		<property name="timeBetweenEvictionRunsMillis" value="30000"/> 
 		<property name="numTestsPerEvictionRun" value="20"/> 
 	 
 
 </bean> 
 
 <bean id="egovaDataSource" class="cn.com.egova.config.EgovaDataSource">
 	<property name="initdataSource" ref="initdataSource"/>
 	<property name="dataSource" ref="realDataSource"/>
 </bean>
 
 
 <bean id="nativeJdbcExtractor" 
 class="org.springframework.jdbc.support.nativejdbc.CommonsDbcpNativeJdbcExtractor"
 lazy-init="true"/>
 <bean id="lobHandler" class="org.springframework.jdbc.support.lob.OracleLobHandler" lazy-init="true"> 
 	 <property name="nativeJdbcExtractor" ref="nativeJdbcExtractor"/>
 </bean>
 
 
 	<bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
 <property name="dataSource" ref="dataSource"/>
 	</bean>
 	<tx:advice id="txAdvice" transaction-manager="txManager">
 		<tx:attributes>
 			
 			<tx:method name="get*" read-only="true" />
 			<tx:method name="load*" read-only="true" />
 			<tx:method name="list*" read-only="true" />
 			<tx:method name="find*" read-only="true" />
 			<tx:method name="*" />
 		</tx:attributes>
 	</tx:advice>
 	<aop:config>
 		 <aop:pointcut id="serviceAllOperation"
 				expression="execution(* cn.com.cd..dao.*Manager.*(..))" />
 	 <aop:advisor advice-ref="txAdvice"
 				pointcut-ref="serviceAllOperation" order="2" />
 	</aop:config>
 	
 	
 <tx:annotation-driven proxy-target-class="true" transaction-manager="txManager"/> 
 
 
 <ehcache:annotation-driven cache-manager="ehCacheManager" /> 
 	<bean id="ehCacheManager" class="org.springframework.cache.ehcache.EhCacheManagerFactoryBean"> 
 <property name="configLocation" value="classpath:ehcache.xml" /> 
 </bean> 
 	
 </beans>

5、配置spring MVC的xml文件\-----application-servlet.xml

5.1 加载spring的全局配置文件

5.2 扫描指定包下的所有类是注解生效

5.3 配置SpringMVC的视图渲染器

<?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:aop="http://www.springframework.org/schema/aop"
 xmlns:mvc="http://www.springframework.org/schema/mvc"
 xsi:schemaLocation="http://www.springframework.org/schema/beans 
 http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
 http://www.springframework.org/schema/context 
 http://www.springframework.org/schema/context/spring-context-3.0.xsd
 http://www.springframework.org/schema/aop
 	http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
 	http://www.springframework.org/schema/mvc
 http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">
 
 
 <context:component-scan base-package="cn.com.cd"/> 
 
 
 	<bean id="mappingJacksonHttpMessageConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"/>
 	<bean class ="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" > 
 	<property name="messageConverters"> 
 	 		<list> 
 	 			<ref bean="mappingJacksonHttpMessageConverter" /> 
 	 		</list> 
 		</property> 
 	</bean>
 	
 
 <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
 	<property name="prefix" value="/view/"/>
 		<property name="suffix" value=".jsp"/>
 </bean>
 
 
 <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
 </bean>
 
 
 <aop:aspectj-autoproxy/>
 
 	
 <mvc:annotation-driven/>
 
 <mvc:resources mapping="/other/**" location="/other/"/>
 <mvc:resources mapping="/library/**" location="/library/"/> 
 
 </beans>

6、写Controller(TestController.java)

7、写jsp文件

执行流程个人总结：接收到请求后会扫描springMVC配置文件中指定的包中的类（controller），根据controller中的注解@RequestMapping("test")找到对应的jsp文件。

二、运行流程

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在整个 Spring MVC框架中，DispatcherServlet处于核心位置，负责协调和组织不同组件以完成请求处理并返回响应的工作  
　　SpringMVC处理请求过程：  
　　1). 若一个请求匹配DispatcherServlet的请求映射路径(在 web.xml 中指定), WEB容器将该请求转交给DispatcherServlet处理  
　　2). DispatcherServlet接收到请求后, 将根据请求信息(包括 URL、HTTP方法、请求头、请求参数、Cookie 等)及HandlerMapping的配置找到处理请求的处理器(Handler).可将HandlerMapping看成路由控制器，将 Handler 看成目标主机。  
　　3). 当DispatcherServlet根据HandlerMapping得到对应当前请求的 Handler后，通过HandlerAdapter对 Handler 进行封装，再以统一的适配器接口调用 Handler。  
　　4). 处理器完成业务逻辑的处理后将返回一个ModelAndView给DispatcherServlet,ModelAndView包含了视图逻辑名和模型数据信息  
　　5). DispatcherServlet借助ViewResoler完成逻辑视图名到真实视图对象的解析  
　　6). 得到真实视图对象 View 后, DispatcherServlet使用这个 View对ModelAndView中的模型数据进行视图渲染。

[Center]: /images/20220724/93c462e53d26424c8bbb62b435feb0ac.png
[Center 1]: /images/20220724/e324727d5f70449b995bc2d895450c3d.png