SpringMVC - 全注解

一、全注解开发

创建web工程配置注解类

@Configuration
public class WebInit extends AbstractAnnotationConfigDispatcherServletInitializer {


    // spring的配置类
    @Override
    protected Class<?>[] getRootConfigClasses() {
        return new Class[]{SpringConfig.class};
    }

    // springmvc的配置类
    @Override
    protected Class<?>[] getServletConfigClasses() {
        return new Class[]{WebConfig.class};
    }


    // 设置DispatcherServlet访问路径
    @Override
    protected String[] getServletMappings() {
        return new String[]{"/"};
    }
}

创建Spring配置注解类

@Configuration
public class SpringConfig {
}

创建SpringMVC配置注解类​

/**
 * springmvc 组件  ：
 *
 *      1. 扫描器
 *      2. 拦截器
 *      3. 异常处理器
 *      4. 默认servlet处理器
 *      5. 文件上传
 *      6. 开启mvc注解
 *      7. mvc:view-controller
 */
@Configuration
// 开启扫描器
@ComponentScan(basePackages = "com.xin")
// 开启mvc
@EnableWebMvc
public class WebConfig implements WebMvcConfigurer {

    // 开启默认servlet处理器
    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
    }

    // 开启mvc:view-controller

    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
        registry.addViewController("/").setViewName("index");
    }

    // 开启异常处理器
    @Override
    public void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> resolvers) {
        SimpleMappingExceptionResolver exceptionResolver = new SimpleMappingExceptionResolver();
        Properties properties = new Properties();
        properties.setProperty("java.lang.NullPointerException","error");
        exceptionResolver.setExceptionMappings(properties);
        resolvers.add(exceptionResolver);
    }

    // 开启拦截器
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        WebMvcConfigurer.super.addInterceptors(registry);
    }

    // 文件上传
    @Bean
    public MultipartResolver getMultipartResolver() {
        return new CommonsMultipartResolver();
    }
}

二、SpringMVC 流程图