SpringMVC知识汇总
- web.xml中的配置
<servlet>
<servlet-name>dispatcherServlet</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>
</servlet>
<servlet-mapping>
<servlet-name>dispatcherServlet</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
<filter>
<filter-name>springSecurityFilterChain</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
<filter-name>springSecurityFilterChain</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<!-- 配置编码的过滤器 -->
<filter>
<filter-name>encoding</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>utf8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
- /*拦截所有的请求
- /拦截除了jsp以外的请求
- <context:component-scan base-package="com.ssw.controller"/>用于扫描@controller注解的包,这样就可以把有@controller注解的类放入到springmvc容器中去
- springmvc是子容器,spring是父容器,子容器能用父容器的bean,相反则不行
- springmvc流程图
- 内部资源解析器:
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="internalResourceViewResolver">
<property name="suffix" value=".jsp"/>
<property name="prefix" value="/jsp/"/>
</bean>
默认是转发,如果是重定向,则这个配置不生效
<mvc:annotation-driven>
<mvc:message-converters>
<bean class="org.springframework.http.converter.StringHttpMessageConverter">
<constructor-arg value="utf-8"/>
</bean>
</mvc:message-converters>
</mvc:annotation-driven>
- requestMappeing注解中method,headers参数是起限制作用的
- requestParam当请求参数和形参名字不一致时用,也可以限制必传等
- requestHeader赋值请求头的信息的 例如:@RequestHeader(“user-agent”,required=true) String useragent
- cookieValue获取cookie的值 例如:@CookieValue(“JESSSION”)String jessionId
- <mvc:default-servlet-handler/>需要和万能模板成对出现才会生效
- xml中的配置
<mvc:interceptors>
<mvc:interceptor>
<mvc:mapping path="/**"/>
<mvc:exclude-mapping path="/show1/show3"/>
//静态资源也要排除掉
<bean class="com.ssw.utils.MyInterceptor" />
</mvc:interceptor>
</mvc:interceptors>
public class MyInterceptor implements HandlerInterceptor {
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
Object ssw = request.getSession().getAttribute("ssw");
if(ssw==null){
request.getRequestDispatcher("/index.jsp").forward(request,response);
return false;}
return true;
}
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, @Nullable ModelAndView modelAndView) throws Exception {
}
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, @Nullable Exception ex) throws Exception {
}
}
- 文件上传三要素:1,post提交。2,form表单文多表单mutipart/formData格式。3,type为file
- 当表单修改为多部分表单时,request.getParamter()将失效
- 在xml中配置:
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<property name="defaultEncoding" value="utf-8"/>
<property name="maxUploadSize" value="5242880"/>
</bean>
public String show2(MultipartFile upload){}
public class MyExceptionResolver implements HandlerExceptionResolver {@Overridepublic ModelAndView resolveException(HttpServletRequest request,HttpServletResponse response, Object handler, Exception ex) {//处理异常的代码实现//创建ModelAndView对象ModelAndView modelAndView = new ModelAndView();modelAndView.setViewName("exceptionPage");return modelAndView;}}
<bean id="exceptionResolver"
class="com.itheima.exception.MyExceptionResolver"/>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
这是一个最终异常的显示页面
</body>
</html>