企业网站推广的实验内容,站长推广网,官方网站怎么注册,专业网页制作软件都能帮助用户组织和管理最近在开发项目时遇到将springmvc无法处理的静态资源请求转发给tomcat默认的servlet进行处理的场景#xff0c;然后根据DispatcherServlet请求的路径#xff0c;找到了如何配置默认Servlet处理器。
一、配置方式
具体需要看您是否使用了springmvc提供的方式完成的注入配置然后根据DispatcherServlet请求的路径找到了如何配置默认Servlet处理器。
一、配置方式
具体需要看您是否使用了springmvc提供的方式完成的注入配置 使用了EnableWebMvc注解使用了SpringBoot中的自动装配org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration.EnableWebMvcConfiguration 这两种方式都是间接的使用了DelegatingWebMvcConfiguration完成了springmvc的配置
针对这种情况可以写一个WebMvcConfigurer接口的实现来完成配置
Component
public class WebMvcConfigurerImpl extends WebMvcConfigurerAdapter {Overridepublic void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {configurer.enable(default);}
}如果您是直接继承WebMvcConfigurationSupport类完成的springmvc配置可以重写父类的方法来完成配置
Configuration
public class WebMvcConfigurationImpl extends WebMvcConfigurationSupport {Overrideprotected void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {configurer.enable(default);}}其中default是tomcat默认的Servlet的名称。
二、原理
要了解此配置的实现机制需要看WebMvcConfigurationSupport中的定义
/*** Return a handler mapping ordered at Integer.MAX_VALUE with a mapped* default servlet handler. To configure default Servlet handling,* override {link #configureDefaultServletHandling}.*/
Bean
public HandlerMapping defaultServletHandlerMapping() {DefaultServletHandlerConfigurer configurer new DefaultServletHandlerConfigurer(this.servletContext);configureDefaultServletHandling(configurer);HandlerMapping handlerMapping configurer.buildHandlerMapping();return (handlerMapping ! null ? handlerMapping : new EmptyHandlerMapping());
}/*** Override this method to configure default Servlet handling.* see DefaultServletHandlerConfigurer*/
protected void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
}类中定义了defaultServletHandlerMapping方法方法中创建了DefaultServletHandlerConfigurer对象使用此对象的buildHandlerMapping方法用于构建一个HandlerMapping对象。 public class DefaultServletHandlerConfigurer {private final ServletContext servletContext;private DefaultServletHttpRequestHandler handler;/*** Create a {link DefaultServletHandlerConfigurer} instance.* param servletContext the ServletContext to use.*/public DefaultServletHandlerConfigurer(ServletContext servletContext) {Assert.notNull(servletContext, ServletContext is required);this.servletContext servletContext;}/*** Enable forwarding to the default Servlet.* pWhen this method is used the {link DefaultServletHttpRequestHandler}* will try to autodetect the default Servlet name. Alternatively, you can* specify the name of the default Servlet via {link #enable(String)}.* see DefaultServletHttpRequestHandler*/public void enable() {enable(null);}/*** Enable forwarding to the default Servlet identified by the given name.* pThis is useful when the default Servlet cannot be autodetected,* for example when it has been manually configured.* see DefaultServletHttpRequestHandler*/public void enable(String defaultServletName) {this.handler new DefaultServletHttpRequestHandler();this.handler.setDefaultServletName(defaultServletName);this.handler.setServletContext(this.servletContext);}/*** Return a handler mapping instance ordered at {link Integer#MAX_VALUE} containing the* {link DefaultServletHttpRequestHandler} instance mapped to {code /**};* or {code null} if default servlet handling was not been enabled.* since 4.3.12*/protected SimpleUrlHandlerMapping buildHandlerMapping() {if (this.handler null) {return null;}SimpleUrlHandlerMapping handlerMapping new SimpleUrlHandlerMapping();handlerMapping.setUrlMap(Collections.singletonMap(/**, this.handler));handlerMapping.setOrder(Integer.MAX_VALUE);return handlerMapping;}/*** deprecated as of 4.3.12, in favor of {link #buildHandlerMapping()}*/Deprecatedprotected AbstractHandlerMapping getHandlerMapping() {return buildHandlerMapping();}}DefaultServletHandlerConfigurer中定义了enable方法enable方法用于创建DefaultServletHttpRequestHandler对象并设置DefaultServletHttpRequestHandler对象的默认Servlet名称和Servlet上下文而buildHandlerMapping方法则用于创建一个SimpleUrlHandlerMapping对象用于处理其余HandlerMapping不能处理的所有请求使用的处理器正是enable方法中创建的DefaultServletHttpRequestHandler对象。 Override
public void handleRequest(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {RequestDispatcher rd this.servletContext.getNamedDispatcher(this.defaultServletName);if (rd null) {throw new IllegalStateException(A RequestDispatcher could not be located for the default servlet this.defaultServletName );}rd.forward(request, response);
}DefaultServletHttpRequestHandler对象中处理请求使用了请求转发。
