【笔记】SpringMVC

1.定义

model view controller
用来简化基于mvc架构的web应用开发框架，是spring框架的一部分

2.架构分层

上层调用下层，通过接口实现，当下层实现发生改变时，不影响上一层

3.工作原理（五大组件的关系）

4.SpringMVC 使用

需要在 web.xml 中配置 DispatcherServlet 。并且需要配置 Spring 监听器ContextLoaderListener

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener
    </listener-class>
</listener>
<servlet>
    <servlet-name>springmvc</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet
    </servlet-class>
    <!-- 如果不设置init-param标签，则必须在/WEB-INF/下创建xxx-servlet.xml文件，其中xxx是servlet-name中配置的名称。 -->
    <init-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:spring/springmvc-servlet.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>springmvc</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>

4.spring-mvc.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: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.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">
 
    <!--配置组件扫描-->
    <context:component-scan base-package="net.wanho.controller"/>
 
    <!--mvc注解扫描，使@RequestMapping起作用-->
    <mvc:annotation-driven>
        <mvc:message-converters>
            <ref bean="fastjsonBean"/>
        </mvc:message-converters>
    </mvc:annotation-driven>
 
    <!--使用fastjson-->
    <bean id="fastjsonBean" class="com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter">
        <property name="supportedMediaTypes">
            <list>
                <value>text/html;charset=UTF-8</value>
                <value>application/json;charset=UTF-8</value>
            </list>
        </property>
        <property name="fastJsonConfig">
            <bean class="com.alibaba.fastjson.support.config.FastJsonConfig">
                <property name="features">
                    <list>
                        <value>AllowArbitraryCommas</value>
                        <value>AllowUnQuotedFieldNames</value>
                        <value>DisableCircularReferenceDetect</value>
                    </list>
                </property>
                <property name="dateFormat" value="yyyy-MM-dd HH:mm:sss"/>
            </bean>
 
        </property>
    </bean>
 
    <!--配置视图解析器-->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/jsp/"/>
        <property name="suffix" value=".jsp"/>
    </bean>
 
    <!--静态资源-->
    <mvc:resources mapping="/img/**" location="/WEB-INF/img/"/>
    <mvc:resources mapping="/css/**" location="/WEB-INF/css/"/>
    <mvc:resources mapping="/js/**" location="/WEB-INF/js/"/>
 
    <!--文件上传-->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="UTF-8"/>
        <property name="maxUploadSize" value="10240000"/>
    </bean>
 
    <!--登录拦截器-->
    <mvc:interceptors>
        <mvc:interceptor>
            <mvc:mapping path="/**"/>
            <mvc:exclude-mapping path="/**/**.html"/>
            <mvc:exclude-mapping path="/**/**.js"/>
            <mvc:exclude-mapping path="/**/**.css"/>
            <mvc:exclude-mapping path="/**/**.jpg"/>
            <mvc:exclude-mapping path="/**/**.png"/>
            <mvc:exclude-mapping path="/**/**.gif"/>
            <bean class="net.wanho.interceptor.LoginInterCeptor"/>     <!--自定义的登陆拦截-->
        </mvc:interceptor>
    </mvc:interceptors>
 
</beans>

5.注解

访问路径=类@RequestMapping url +方法url

@Controller
@RequestMapping("/appointments")
public class AppointmentsController {
	@RequestMapping(value="/new", method = RequestMethod.GET)
    public AppointmentForm getNewForm(@RequestParam("id") String personId) {
        return new AppointmentForm();
    }
}

6.重定向与转发

@RequestMapping("/testRedirect")
public String testRedirect(){
	System.out.println("testRedirect");
	// 重定向
	return "redirect:/index.do";
	// 转发
	//return "forward:/index.jsp";
}

7.interceptor

流程

优先级

当有多个拦截器满足要求时，依据配置的先后顺序来执行

filter与interceptor的区别

1. filter属于servlet规范，在web.xml中配置，拦截servlet容器的调用过程
2. interceptor属于spring框架，在spring-mvc.xml中配置，拦截DispatcherServlet的调用过程

8.exceptionHandler