分析讲解SpringMVC注解配置如何实现

package com.hxut.rj1192.annoation;

import org.springframework.web.filter.CharacterEncodingFilter;

import org.springframework.web.filter.HiddenHttpMethodFilter;

import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;

import javax.servlet.Filter;

//代替web.xml   filter过滤器   spring  springmvc的配置类    dispracture的映射路径

public class webXml extends AbstractAnnotationConfigDispatcherServletInitializer {

     //    指定spring配置类

     @Override

     protected Class<?>[] getRootConfigClasses() {

         return new Class[] {SpringConfig. class };

     }

     //    指定springmvc配置类

     @Override

     protected Class<?>[] getServletConfigClasses() {

         return new Class[]{SpringMvcConfig. class };

     }

     //    指定dispracture的映射路径 即url-pattern

     @Override

     protected String[] getServletMappings() {

         return new String[]{ "/" };

     }

//注册编码过滤器

     @Override

     protected Filter[] getServletFilters() {

         CharacterEncodingFilter encodingFilter = new CharacterEncodingFilter();

         encodingFilter.setEncoding( "UTF-8" );

         encodingFilter.setForceRequestEncoding( true );

         HiddenHttpMethodFilter hiddenHttpMethodFilter = new HiddenHttpMethodFilter();

         return new Filter[]{encodingFilter, hiddenHttpMethodFilter};

     }

}

package com.hxut.rj1192.annoation;

import com.hxut.rj1192.InterceptorRegistry01;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.ComponentScan;

import org.springframework.context.annotation.Configuration;

import org.springframework.web.context.ContextLoader;

import org.springframework.web.context.WebApplicationContext;

import org.springframework.web.multipart.commons.CommonsMultipartResolver;

import org.springframework.web.servlet.HandlerExceptionResolver;

import org.springframework.web.servlet.HandlerInterceptor;

import org.springframework.web.servlet.ViewResolver;

import org.springframework.web.servlet.config.annotation.*;

import org.springframework.web.servlet.handler.SimpleMappingExceptionResolver;

import org.thymeleaf.spring5.SpringTemplateEngine;

import org.thymeleaf.spring5.view.ThymeleafViewResolver;

import org.thymeleaf.templatemode.TemplateMode;

import org.thymeleaf.templateresolver.ITemplateResolver;

import org.thymeleaf.templateresolver.ServletContextTemplateResolver;

import java.util.List;

import java.util.Properties;

//1视图解析器   2扫描包的范围（组件扫描）  3view-controller（只返回视图的控制方法）  4defalut-servlet-handler  静态资源处理和

//5  mvc注解驱动  6文件上传解析器   7异常处理   8拦截器

//代替springmvc的配置文件

//扫描包的范围（组件扫描）

@ComponentScan ( "com.hxut.rj1192" )

//开启MVC注解驱动

@EnableWebMvc

@Configuration

public class SpringMvcConfig implements WebMvcConfigurer {

     //配置视图解析器

//    这个注解是将类放进ioc容器中  因为web.xml中就是嵌套的,

     @Bean

     public ITemplateResolver templateResolver() {

         WebApplicationContext webApplicationContext = ContextLoader.getCurrentWebApplicationContext();

         // ServletContextTemplateResolver需要一个ServletContext作为构造参数，可通过WebApplicationContext 的方法获得

         ServletContextTemplateResolver templateResolver = new ServletContextTemplateResolver(

                 webApplicationContext.getServletContext());

         templateResolver.setPrefix( "/WEB-INF/templates/" );

         templateResolver.setSuffix( ".html" );

         templateResolver.setCharacterEncoding( "UTF-8" );

         templateResolver.setTemplateMode(TemplateMode.HTML);

         return templateResolver;

     }

     //生成模板引擎并为模板引擎注入模板解析器

     @Bean

     public SpringTemplateEngine templateEngine(ITemplateResolver templateResolver) {

         SpringTemplateEngine templateEngine = new SpringTemplateEngine();

         templateEngine.setTemplateResolver(templateResolver);

         return templateEngine;

     }

     //生成视图解析器并未解析器注入模板引擎

     @Bean

     public ViewResolver viewResolver(SpringTemplateEngine templateEngine) {

         ThymeleafViewResolver viewResolver = new ThymeleafViewResolver();

         viewResolver.setCharacterEncoding( "UTF-8" );

         viewResolver.setTemplateEngine(templateEngine);

         return viewResolver;

     }

//default-servlet configuure

     @Override

     public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {

         WebMvcConfigurer. super .configureDefaultServletHandling(configurer);

     }

     @Override

     public void addInterceptors(InterceptorRegistry registry) {

         InterceptorRegistry01 interceptorRegistry= new InterceptorRegistry01();

//        addPathPatterns("/");是设置拦截的url

//        excludePathPatterns(); 是设置不拦截的url

         registry.addInterceptor(interceptorRegistry).addPathPatterns( "/" );

     }

//视图控制器

     @Override

     public void addViewControllers(ViewControllerRegistry registry) {

       registry.addViewController( "/hello" ).setViewName( "succes" );

     }

     //配置文件上传解析器

     @Bean

     public CommonsMultipartResolver multipartResolver(){

         CommonsMultipartResolver commonsMultipartResolver= new CommonsMultipartResolver();

         return commonsMultipartResolver;

     }

     //配置异常映射

     @Override

     public void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> resolvers) {

         SimpleMappingExceptionResolver exceptionResolver = new SimpleMappingExceptionResolver();

         Properties prop = new Properties();

         prop.setProperty( "java.lang.ArithmeticException" , "error" );

         //设置异常映射

         exceptionResolver.setExceptionMappings(prop);

         //设置共享异常信息的键

         exceptionResolver.setExceptionAttribute( "ex" );

         resolvers.add(exceptionResolver);

     }

}

<? 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 https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd" >

       <!--2.扫描包的范围（组件扫描）-->

     < context:component-scan base-package = "com.hxut.rj1192.zyk" />

     <!-- 1.配置Thymeleaf视图解析器 -->

     < bean id = "viewResolver" class = "org.thymeleaf.spring5.view.ThymeleafViewResolver" >

         < property name = "order" value = "1" />

         < property name = "characterEncoding" value = "UTF-8" />

         < property name = "templateEngine" >

             < bean class = "org.thymeleaf.spring5.SpringTemplateEngine" >

                 < property name = "templateResolver" >

                     < bean class = "org.thymeleaf.spring5.templateresolver.SpringResourceTemplateResolver" >

                         < property name = "prefix" value = "/WEB-INF/templates/" />

                         < property name = "suffix" value = ".html" />

                         < property name = "templateMode" value = "HTML5" />

                         < property name = "characterEncoding" value = "UTF-8" />

                     </ bean >

                 </ property >

             </ bean >

         </ property >

     </ bean >

     <!--4.静态资源处理-->

     < mvc:default-servlet-handler />

     <!--5.mvc注解驱动-->

     < mvc:annotation-driven />

< mvc:interceptors >

     < bean class = "com.hxut.rj1192.zyk.interceptor.interceptor01" />

</ mvc:interceptors >

     < bean class = "org.springframework.web.servlet.handler.SimpleMappingExceptionResolver" >

         < property name = "exceptionMappings" >

             < props >

                 < prop key = "java.lang.ArithmeticException" >error</ prop >

             </ props >

         </ property >

         < property name = "exceptionAttribute" value = "ex" ></ property >

     </ bean >

<! --3.view-controller-->

< mvc:view-controller path = "/testView" view-name = "success" ></ mvc:view-controller >

<! --4.文件上传解析器-->

     < bean id = "multipartResolver"

           class = "org.springframework.web.multipart.commons.CommonsMultipartResolver" >

     </ bean >

<! --7.异常处理-->

     < bean class = "org.springframework.web.servlet.handler.SimpleMappingExceptionResolver" >

             < property name = "exceptionMappings" >

                 < props >

                     < prop key = "java.lang.ArithmeticException" >error</ prop >

                 </ props >

             </ property >

             <!--        将错误信息放到ex这个变量中，并放进model中-->

             < property name = "exceptionAttribute" value = "ex" ></ property >

         </ bean >

<! --8.拦截器-->

  < mvc:interceptors >

         < ref bean = "first" ></ ref >

         < ref bean = "second" ></ ref >

     </ mvc:interceptors >

</ beans >

package com.hxut.rj1192;

import org.springframework.web.servlet.HandlerInterceptor;

import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

public class InterceptorRegistry01 implements HandlerInterceptor {

     @Override

     public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {

         System.out.println( "prehandle 执行" );

         return true ;

     }

     @Override

     public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

         System.out.println( "posthandle 执行" );

         HandlerInterceptor. super .postHandle(request, response, handler, modelAndView);

     }

     @Override

     public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

         System.out.println( "afterhandle 执行" );

         HandlerInterceptor. super .afterCompletion(request, response, handler, ex);

     }

}