web.xml,其绝对路径为: \com.mimvp.homer\src\main\webapp\WEB-INF\web.xml

通过查看log4j的日志可以发现在服务器启动时 applicationContext.xml 是先于spring3-servlet.xml 加载

[org.springframework.web.context.ContextLoader] - Root WebApplicationContext: initialization started
May 22, 2017 4:55:25 PM org.apache.catalina.core.ApplicationContext log
信息: Initializing Spring root WebApplicationContext
[org.springframework.web.context.support.XmlWebApplicationContext] - Refreshing Root WebApplicationContext: startup date [Mon May 22 16:55:25 CST 2017]; root of context hierarchy
[org.springframework.beans.factory.xml.XmlBeanDefinitionReader] - Loading XML bean definitions from class path resource [spring-mybatis.xml]
[org.springframework.beans.factory.config.PropertyPlaceholderConfigurer] - Loading properties file from class path resource [jdbc.properties]
[org.springframework.web.context.ContextLoader] - Root WebApplicationContext: initialization completed in 5058 ms
May 22, 2017 4:55:30 PM org.apache.catalina.core.ApplicationContext log
信息: Initializing Spring FrameworkServlet 'SpringMVC'
[org.springframework.web.servlet.DispatcherServlet] - FrameworkServlet 'SpringMVC': initialization started
[org.springframework.web.context.support.XmlWebApplicationContext] - Refreshing WebApplicationContext for namespace 'SpringMVC-servlet': startup date [Mon May 22 16:55:30 CST 2017]; parent: Root WebApplicationContext
[org.springframework.beans.factory.xml.XmlBeanDefinitionReader] - Loading XML bean definitions from class path resource [spring-mvc.xml]
[org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping] - Mapped URL path [/user/showPwd] onto handler 'userController'
[org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping] - Mapped URL path [/user/showPwd.*] onto handler 'userController'
[org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping] - Mapped URL path [/user/showPwd/] onto handler 'userController'
[org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping] - Mapped URL path [/user/showUser] onto handler 'userController'
[org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping] - Mapped URL path [/user/showUser.*] onto handler 'userController'
[org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping] - Mapped URL path [/user/showUser/] onto handler 'userController'
[org.springframework.web.servlet.DispatcherServlet] - FrameworkServlet 'SpringMVC': initialization completed in 1913 ms
May 22, 2017 4:55:32 PM org.apache.catalina.startup.HostConfig deployDescriptor
信息: Deployment of configuration descriptor E:\myPro\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\conf\Catalina\localhost\com.mimvp.homer.xml has finished in 13,551 ms
May 22, 2017 4:55:32 PM org.apache.coyote.AbstractProtocol start
信息: Starting ProtocolHandler ["http-bio-8080"]
May 22, 2017 4:55:32 PM org.apache.coyote.AbstractProtocol start
信息: Starting ProtocolHandler ["ajp-bio-8009"]
May 22, 2017 4:55:32 PM org.apache.catalina.startup.Catalina start
信息: Server startup in 21873 ms
[com.mimvp.homer.controller.UserController] - /showUser?id=1
[com.mimvp.homer.controller.UserController] - /showPwd?id=3

Spring MVC 加载顺序依次为: 

ContextLoader —> XmlWebApplicationContext —> XmlBeanDefinitionReader —> PropertyPlaceholderConfigurer —> ContextLoader (完成)

DispatcherServlet —> XmlWebApplicationContext —> XmlBeanDefinitionReader —> DefaultAnnotationHandlerMapping —> DispatcherServlet (完成)

因此,applicationContext.xml 中已经注册到BeanFactory的bean,在spring3-servlet.xml也是可以使用的,比如在applicationContext.xml中通过context:component-scan扫描了service和dao包,而在spring3-servlet.xml只扫描了web包,但web包中的Controller依然被注入了Service

web.xml各个标签的加载顺序:context-param -> listener -> filter -> servlet

 

ContextLoaderListener 类源码

package org.springframework.web.context;

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;

public class ContextLoaderListener extends ContextLoader implements ServletContextListener {
	public ContextLoaderListener() {
	}

	public ContextLoaderListener(WebApplicationContext context) {
		super(context);
	}

	/**
	 * Initialize the root web application context.
	 */
	@Override
	public void contextInitialized(ServletContextEvent event) {
		initWebApplicationContext(event.getServletContext());
	}

	/**
	 * Close the root web application context.
	 */
	@Override
	public void contextDestroyed(ServletContextEvent event) {
		closeWebApplicationContext(event.getServletContext());
		ContextCleanupListener.cleanupAttributes(event.getServletContext());
	}

}

ContextLoaderListener 有两个构造函数,继承于ContextLoader类,实现了ContextLoader接口及其两个方法。

 

web.xml

<?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" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    version="2.5">
	
    <!-- 初始化Spring容器, 并加载Spring配置文件applicationContext.xml -->
    <context-param>
         <param-name>contextConfigLocation</param-name>
         <param-value>classpath:com/mimvp/config/applicationContext.xml</param-value>
    </context-param>
	
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
	
    <!-- 使用filter来统一字符编码 -->
    <filter>
        <filter-name>Set Character 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>
        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>Set Character Encoding</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!-- 加载DispatcherServlet并加载其的配置文件spring3-servlet.xml -->
    <servlet>
        <servlet-name>spring3</servlet-name>        <!-- 默认找到的是spring3-servlet.xml -->
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <!-- 
		<init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:com/mimvp/config/spring3-servlet.xml</param-value>
        </init-param> 
		-->
        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
        <servlet-name>spring3</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
    <servlet-mapping>
        <servlet-name>spring3</servlet-name>
        <url-pattern>*.html</url-pattern>
    </servlet-mapping>

    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
</web-app>

启动加载文件 web.xml,会加载配置文件 applicationContext.xml 和 spring3-servlet.xml

 

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-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://www.springframework.org/schema/aop

		http://www.springframework.org/schema/aop/spring-aop-3.0.xsd" 
		default-autowire="byName">
		
    <!-- 注意上面的default-autowire="byName",如果没有这个声明那么HibernateDaoSupport中的sessionFactory不会被注入 -->
    <!-- 约定优于配置-->

    <!-- 
	自动扫描组件,包括@Controller,@Service,@Repository这里要把web下面的 controller去除,他们已经在spring3-servlet.xml中配置了,也就是已经加入beanFactory,否则会影响注入 
	-->
	
    <!-- 还发现了一个问题,就是如果不扫描@Repository,页面都进不去,报404,后来发现是这里的default-autowire和Javabean中@Autowire有冲突。。但最后还是要扫描@Repository,因为要给DAO注入sessionFactory 
	-->
    <context:component-scan base-package="com.mimvp">
        <context:exclude-filter type="regex" expression="com.mimvp.web.*" />
    </context:component-scan>
	
    <!-- 
	<context:component-scan base-package="com.mimvp.service.impl"></context:component-scan>
    <context:component-scan base-package="com.mimvp.dao.impl"></context:component-scan> 
	-->
    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://127.0.0.1:3306/ytcdb2?useUnicode=true&amp;characterEncoding=UTF-8"></property>
        <property name="username" value="root"></property>
        <property name="password" value="root"></property>
        <!-- 为了不用每次都去数据库,可以在这里配置连接池,当然,还要引入响应的jar包 -->
		<property name="maxActive" value="10"></property>
        <property name="maxWait" value="60000"></property>
        <property name="maxIdle" value="5"></property> 
    </bean>

    <bean id="sessionFactory"
        class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <!-- 由于通过autowire启用了自动装载,所以下面的这个dataSource其实是可以不用写的 ,后面通过ref引用的都是一样的道理-->
        <property name="dataSource" ref="dataSource" />
        <property name="mappingDirectoryLocations">
            <list><!-- 这里直接映射的pojo类所在的包,简单方便不用每次加一个pojo类都需要到这里来添加 -->
                <value>classpath:com/mimvp/model</value>
            </list>
        </property>
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
                <prop key="hibernate.show_sql">true</prop>
                <prop key="hibernate.connection.autocommit">true</prop>
            </props>
        </property>
    </bean>

    <!-- 下面是配置声明式事务管理的,个人感觉比用注解管理事务要简单方便 -->
    <bean id="txManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory" ref="sessionFactory"></property>
    </bean>

	<!-- advisor包含一个切点和一个通知,而aspect包含多个 -->
    <aop:config>
		<aop:advisor pointcut="execution(* com.mimvp.service.*Service.*(..))" advice-ref="txAdvice" />
    </aop:config>

    <tx:advice id="txAdvice" transaction-manager="txManager">
        <tx:attributes>
        <!-- Service类中以get*,query*等等开头的查询操作只能执行只读事务;对于所有的事务,如果出现异常就回滚 -->
            <tx:method name="get*" read-only="true" />
            <tx:method name="query*" read-only="true" />
            <tx:method name="find*" read-only="true" />
            <tx:method name="load*" read-only="true" />
            <tx:method name="*" rollback-for="Exception" />
        </tx:attributes>
    </tx:advice>
</beans>

 

spring3-servlet.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:p="http://www.springframework.org/schema/p"
    xmlns:context="http://www.springframework.org/schema/context"
    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/mvc

           http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd"
    default-autowire="byName">  <!-- default-autowire="byName",约定优于配置 -->
    <!--mvc:annotation-driven注册了 RequestMappingHandlerMapping, a RequestMappingHandlerAdapter,and an ExceptionHandlerExceptionResolver 
        能启动@RequestMapping,@ExceptionHandler, and others注释 -->
    <mvc:annotation-driven />
    <!-- 把无法mapping到Controller的path交给default servlet handler处理 -->
    <mvc:default-servlet-handler />
    <!-- 配置静态资源,直接映射到对应的文件夹,不被DispatcherServlet处理而由前面的default-servlet-handler处理,3.04新增功能,需要重新设置spring-mvc-3.0.xsd -->
    <mvc:resources mapping="/img/**" location="/img/" />
    <mvc:resources mapping="/js/**" location="/js/" />
    <mvc:resources mapping="/css/**" location="/css/" />
    <mvc:resources mapping="/html/**" location="/html/" />

    <!-- ①:对web包中的Controller类进行扫描,以完成Bean创建和自动依赖注入的功能 -->
    <!-- 也就是说这里相当于实例化了Controller类并且给它注入了Service的实例?它没有扫描Service的包诶。。 -->
    <!-- 因为applicationContext.xml先于本文件加载,所以那边先进行扫描,其实是注入了的,byName通过@Service(...)里面的值进行匹配 -->
    <context:component-scan base-package="com.mimvp.web" />

    <!--- StringHttpMessageConverter bean -->

    <!-- 下面这两个处理器映射默认跟<mvc:annotation-driven />功能几乎是一样的,都能够启用SpringMVC的注解功能,只是如果要添加一些其它功能的时候就进行配置了 -->
    <!-- ②:启动Spring MVC的注解功能,完成请求和注解POJO的映射,添加拦截器,类级别的处理器映射 -->
    <bean
        class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
        <property name="interceptors">
            <list>
            <!-- 用于检查session是否存在 -->
                <bean class="com.mimvp.util.MyHandlerInterceptor" />
            </list>
        </property>
    </bean>

    <!-- ②:启动Spring MVC的注解功能,完成请求和注解POJO的映射,对有RequestMapping注解的控制器进行HTTP路径、HTTP方法和请求参数解析,
        这里 配置了一个基于注解的定制的WebBindingInitializer,解决日期转换问题,方法级别的处理器映射 -->
    <bean
        class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
        <property name="cacheSeconds" value="0" />
        <!-- cacheSeconds =0时,则将设置如下响应头数据: 
        Pragma:no-cache     HTTP 1.0的不缓存响应头
        Expires:1L          useExpiresHeader=true时,HTTP 1.0 
        Cache-Control :no-cache  useCacheControlHeader=true时,HTTP 1.1 
        Cache-Control :no-store  useCacheControlNoStore=true时,该设置是防止Firefox缓存 -->
        <property name="webBindingInitializer">
            <bean class="com.mimvp.util.MyWebBinding" />
        </property>
        <!-- 配置一下对json数据的转换 -->
        <property name="messageConverters">
            <list>
                <!-- 对@ResponseBody注释的方法生效 -->
                <bean
                    class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"></bean>
                <bean
                    class="org.springframework.http.converter.StringHttpMessageConverter" />
            </list>
        </property>
    </bean>

    <!-- 配置对JSP文件的视图解析器 -->
    <bean id="freemarkerConfig"
        class="org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer">
        <property name="templateLoaderPath" value="/WEB-INF/view/" />
        <property name="freemarkerSettings">
            <props>
                <prop key="template_update_delay">0</prop>
                <prop key="default_encoding">UTF-8</prop>
                <prop key="number_format">0.##########</prop>
                <prop key="datetime_format">yyyy-MM-dd HH:mm:ss</prop>
                <prop key="classic_compatible">true</prop>
                <prop key="template_exception_handler">ignore</prop>
            </props>
        </property>
    </bean>

    <bean id="viewResolverJsp"
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/view/" />
        <property name="suffix" value=".jsp" />
        <property name="viewClass"
            value="org.springframework.web.servlet.view.InternalResourceView" />
        <property name="order" value="1" />
    </bean>
    <!-- 配置对HTML文件的视图解析器 -->
    <!-- 设置freeMarker的配置文件路径 -->
    <bean id="freemarkerConfiguration"
        class="org.springframework.beans.factory.config.PropertiesFactoryBean">
    </bean>

    <bean id="viewResolver"
        class="org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver">
        <property name="exposeRequestAttributes" value="true" />
        <property name="exposeSessionAttributes" value="true" />
        <property name="viewClass">
            <value>org.springframework.web.servlet.view.freemarker.FreeMarkerView
            </value>
        </property>
        <property name="cache">
            <value>true</value>
        </property>
        <!-- <property name="allowSessionOverride" value="true" /> -->
        <property name="suffix">
            <value>.html</value>
        </property>
        <!-- <property name="viewNames" value="*.html,*.jsp" /> -->
        <property name="contentType">
            <value>text/html; charset=UTF-8</value>
        </property>
        <property name="order" value="0" />
    </bean>
</beans> 

 

 

参考推荐

Maven 构建 Spring MVC 项目的简单示例

Java中Dao层、Action层、Service层、Controller层

SpringMVC 启动过程详解