springmvc最为人称道的就是过多的xml配置，繁琐且复杂，本文将按照加载顺序逐一介绍配置，附上文件结构。
1.加载web.xml
启动时，第一步加载web.xml，初始化上线文与核心控制器DispatcherServlet 。
<?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" version="3.0"> <display-name>Archetype Created Web Application</display-name> <welcome-file-list> <welcome-file>/index.jsp</welcome-file> </welcome-file-list> <!-- 加载applicationContext.xml配置文件 --> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext.xml</param-value> </context-param> <!-- 创建WebApplicationContext（上下文） --> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <!-- 编码过滤器 --> <filter> <filter-name>encodingFilter</filter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class> <async-supported>true</async-supported> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> </filter> <filter-mapping> <filter-name>encodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <!-- 加载DispatcherServlet --> <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-mvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> <async-supported>true</async-supported> </servlet> <servlet-mapping> <servlet-name>SpringMVC</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> </web-app>
2.读取applicationContext.xml
之后，会读取 applicationContext.xml，该xml中引用了spring-dao.xml，spring-db.xml，spring-tx.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:tx="http://www.springframework.org/schema/tx" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:websocket="http://www.springframework.org/schema/websocket" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/websocket http://www.springframework.org/schema/websocket/spring-websocket.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsd http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd"> <!-- 自动扫描 读取各个类的spring注解 并注入spring工厂中 使项目支持依赖注入 --> <context:component-scan base-package="com" /> <!-- 导入DAO配置 --> <import resource="spring-dao.xml" /> <!-- 导入数据库配置 --> <import resource="spring-db.xml" /> <!-- 导入事务配置 --> <import resource="spring-tx.xml" /> </beans>
3.读取spring-dao.xml
mybatis配置，获取dao层所在的位置。
<?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:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- DAO接口所在包名，Spring会自动查找其下的类 并且将所有的dao接口封装成beanDefinitions(spring bean) 装载进入spring factory --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!--basePackage指定要扫描的包，在此包之下的映射器都会被搜索到。 可指定多个包，包与包之间用逗号或分号分隔--> <property name="basePackage" value="com.dao" /> <!-- spring-db.xml中的 sqlSessionFactory--> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean> </beans>
4.读取 spring-db.xml
这里是配置数据库连接与mybatis的相关配置。。
<?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:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- 引入配置文件 配置的数据库信息--> <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="location" value="classpath:jdbc.properties" /> </bean> <!-- 数据库连接池 --> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${driver}" /> <property name="url" value="${url}" /> <property name="username" value="root" /> <property name="password" value="root" /> <!-- 初始化连接大小 --> <property name="initialSize" value="${initialSize}"></property> <!-- 连接池最大数量 --> <property name="maxActive" value="${maxActive}"></property> <!-- 连接池最大空闲 --> <property name="maxIdle" value="${maxIdle}"></property> <!-- 连接池最小空闲 --> <property name="minIdle" value="${minIdle}"></property> <!-- 获取连接最大等待时间 --> <property name="maxWait" value="${maxWait}"></property> </bean> <!-- spring和MyBatis完美整合，不需要mybatis的配置映射文件 将mapper.xml解析成SqlSessionFactoryBean并返回，在查询时 可以获取SqlSessionFactory，并通过代理模调用到--> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 引入mysql数据源 --> <property name="dataSource" ref="dataSource" /> <!-- 自动扫描mapping.xml文件 --> <property name="mapperLocations" value="classpath:com/mappers/*.xml"></property> </bean> </beans>
这里连接数据库需要知道数据库的账号密码，为了统一管理，将数据库配置放在jdbc.properties。
driver=com.mysql.jdbc.Driver url=jdbc:mysql://localhost:3306/mysql username=root password=root initialSize=0 maxActive=20 maxIdle=20 minIdle=1 maxWait=60000
5.读取spring-tx.xml
进行事务配置 通过applicationContext.xml读取的配置到这就结束了。
<?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" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsd http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"> <!-- (事务管理)transaction manager, use JtaTransactionManager for global tx --> <!-- 如果在同一个service类中定义的两个方法， 内层REQUIRES_NEW并不会开启新的事务，save和update中回滚都会导致整个事务的回滚 如果在不同的service中定义的两个方法， 内层REQUIRES_NEW会开启新的事务，并且二者独立，事务回滚互不影响 --> <!-- <tx:annotation-driven transaction-manager="transactionManager" /> --> <!-- Spring编程式事务 --> <tx:advice id="txAdvice" transaction-manager="transactionManager"> <tx:attributes> <tx:method name="insertInto" propagation="REQUIRED" read-only="false" rollback-for="java.lang.Exception" /> </tx:attributes> </tx:advice> <!-- 事务处理管理器 --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <!-- 为spring-db.xml中dataSource数据库连接池 --> <property name="dataSource" ref="dataSource" /> </bean> </beans>
6.读取spring-mvc.xml
该配置主要是配置spring mvc核心功能，如aop，注解扫描位置，拦截器等。
<?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:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:task="http://www.springframework.org/schema/task" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd"> <!--避免IE执行AJAX时，返回JSON出现下载文件 --> <bean id="mappingJacksonHttpMessageConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"> <property name="supportedMediaTypes"> <list> <value>text/html;charset=UTF-8</value> </list> </property> </bean> <!-- 添加注解驱动 --> <mvc:annotation-driven /> <!-- 设置使用注解的类所在的包 mvc只需要扫描controller就可以--> <context:component-scan base-package="com.controller" /> <!-- 完成请求和注解POJO的映射 --> <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"> <property name="messageConverters"> <list> <ref bean="mappingJacksonHttpMessageConverter" /> <!-- JSON转换器 --> </list> </property> </bean> <!-- 定义跳转的文件的前后缀 ，视图模式配置 由于现在基本都是前后端分离 一般没什么软用 --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <!-- 这里的配置我的理解是自动给后面action的方法return的字符串加上前缀和后缀，变成一个 可用的url地址 --> <property name="prefix" value="/WEB-INF/jsp/" /> <property name="suffix" value=".jsp" /> </bean> <!-- SpringMVC上传文件时，需要配置MultipartResolver处理器 --> <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <!-- 默认编码 --> <property name="defaultEncoding" value="utf-8" /> <!-- 文件大小最大值 --> <property name="maxUploadSize" value="10485760000" /> <!-- 内存中的最大值 --> <property name="maxInMemorySize" value="40960" /> </bean> <!-- aop的配置 --> <aop:aspectj-autoproxy></aop:aspectj-autoproxy> <!-- 定时任务配置 --> <task:executor id="executor" pool-size="10" queue-capacity="128" /> <task:scheduler id="scheduler" pool-size="10" /> <task:annotation-driven executor="executor" scheduler="scheduler" proxy-target-class="true" /> <!-- 拦截器配置 --> <mvc:interceptors> <mvc:interceptor> <!--配置拦截器的作用路径 --> <mvc:mapping path="/**" /> <!--定义在<mvc:interceptor>下面的表示匹配指定路径的请求才进行拦截 com.HandlerInterceptor为拦截器类名 --> <bean class="com.HandlerInterceptor" /> </mvc:interceptor> </mvc:interceptors> </beans>
7.拦截器类
import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.stereotype.Component; import org.springframework.web.servlet.ModelAndView; import org.springframework.web.servlet.handler.HandlerInterceptorAdapter; @Component public class HandlerInterceptor extends HandlerInterceptorAdapter { public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception { System.out.println("11111111"); } public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception { System.out.println("222222222"); } public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception { System.out.println("333333333"); return true; } }
8.aop切面
import java.util.Arrays; import javax.servlet.http.HttpServletRequest; import org.aspectj.lang.JoinPoint; import org.aspectj.lang.ProceedingJoinPoint; import org.aspectj.lang.annotation.AfterReturning; import org.aspectj.lang.annotation.Around; import org.aspectj.lang.annotation.Aspect; import org.aspectj.lang.annotation.Before; import org.aspectj.lang.annotation.Pointcut; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.context.annotation.Configuration; import org.springframework.web.context.request.RequestContextHolder; import org.springframework.web.context.request.ServletRequestAttributes; @Aspect @Configuration public class IntercepterInterface { private static final Logger LOG = LoggerFactory.getLogger(IntercepterInterface.class); @Pointcut("execution(* com.controller.*.*(..))") public void logPointCut() { } @Before("logPointCut()") public void doBefore(JoinPoint joinPoint) throws Throwable { ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes(); HttpServletRequest request = attributes.getRequest(); LOG.info("HTTP METHOD : " + request.getMethod()); LOG.info("IP : " + request.getRemoteAddr()); LOG.info("CLASS_METHOD : " + joinPoint.getSignature().getDeclaringTypeName() + "." + joinPoint.getSignature().getName()); System.out.println("aaa"); } @AfterReturning(returning = "ret", pointcut = "logPointCut()") public void doAfterReturning(Object ret) throws Throwable { System.out.println("bbb"); } @Around("logPointCut()") public Object doAround(ProceedingJoinPoint pjp) throws Throwable { long startTime = System.currentTimeMillis(); Object ob = pjp.proceed(); System.out.println("ccc"); return ob; } }
