注解配置SpringMVC

创建WebInit类，继承AbstractAnnotationConfigDispatcherServletInitializer

//web工程的初始化类，用来代替web.xml
public class WebInit extends AbstractAnnotationConfigDispatcherServletInitializer {
    
    protected Class[] getRootConfigClasses() {
        return new Class[]{SpringConfig.class};
    }
    
    protected Class[] getServletConfigClasses() {
        return new Class[]{WebConfig.class};
    }
    
    protected String[] getServletMappings() {
        return new String[]{"/"};
    }

    
    @Override
    protected Filter[] getServletFilters() {
        CharacterEncodingFilter characterEncodingFilter = new CharacterEncodingFilter();
        characterEncodingFilter.setEncoding("UTF-8");
        characterEncodingFilter.setForceResponseEncoding(true);
        HiddenHttpMethodFilter hiddenHttpMethodFilter = new HiddenHttpMethodFilter();
        return new Filter[]{characterEncodingFilter,hiddenHttpMethodFilter};
    }
}

创建WebConfig配置类，代替SpringMVC的配置文件

@Configuration
public class WebConfig {

}

//1、扫描组件
@ComponentScan("com.atguigu.mvc.controller")
public class WebConfig {
}

@Configuration
//1、扫描组件
@ComponentScan("com.atguigu.mvc.controller")
//5、mvc注解驱动
@EnableWebMvc
public class WebConfig {

    //配置生成模板解析器
    @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;
    }

}

    public void addViewControllers(ViewControllerRegistry registry) {
        registry.addViewController("/hello").setViewName("hello");
    }

    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        //4、default-servlet-handler
        configurer.enable();
    }

//1、扫描组件
@ComponentScan("com.atguigu.mvc.controller")
//5、mvc注解驱动
@EnableWebMvc
public class WebConfig {
}

    //6、文件上传解析器
    @Bean
    public MultipartResolver multipartResolver(){
        CommonsMultipartResolver commonsMultipartResolver  = new CommonsMultipartResolver();
        return commonsMultipartResolver;
    }

    //7、异常处理
    public void configureHandlerExceptionResolvers(List resolvers) {
        SimpleMappingExceptionResolver simpleMappingExceptionResolver = new SimpleMappingExceptionResolver();
        Properties prop = new Properties();
        prop.setProperty("java.lang.ArithmeticException","error");
        simpleMappingExceptionResolver.setExceptionMappings(prop);
        simpleMappingExceptionResolver.setExceptionAttribute("exception");
        resolvers.add(simpleMappingExceptionResolver);
    }

    public void addInterceptors(InterceptorRegistry registry) {
        TestInterceptor testInterceptor = new TestInterceptor();
        // /*表示一层
        // /**表示所有
        registry.addInterceptor(testInterceptor).addPathPatterns("/**");
    }

TestInterceptor类

public class TestInterceptor implements HandlerInterceptor {
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("TestInterceptor preHandle");
        return false;
    }

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

    }

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

    }
}