SpringBoot 2.0使用 WebMvcConfigurer 添加

SpringBoot 2.0使用 WebMvcConfigurer 添加攔截器
問題：

以前項目是springboot1.5版本的,後來想升級一下用2.0,可是在升級事後發現WebMvcConfigurerAdapter抽象類過期了

[Java] 純文本查看 複製代碼
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@Deprecated
public abstract class WebMvcConfigurerAdapter implements WebMvcConfigurer {

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void configurePathMatch(PathMatchConfigurer configurer) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void configureContentNegotiation(ContentNegotiationConfigurer configurer) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void configureAsyncSupport(AsyncSupportConfigurer configurer) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void addFormatters(FormatterRegistry registry) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void addInterceptors(InterceptorRegistry registry) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void addCorsMappings(CorsRegistry registry) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void addViewControllers(ViewControllerRegistry registry) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void configureViewResolvers(ViewResolverRegistry registry) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void addArgumentResolvers(List<HandlerMethodArgumentResolver> argumentResolvers) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void addReturnValueHandlers(List<HandlerMethodReturnValueHandler> returnValueHandlers) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> exceptionResolvers) {
}

/**
 * {@inheritDoc}
 * <p>This implementation is empty.
 */
@Override
public void extendHandlerExceptionResolvers(List<HandlerExceptionResolver> exceptionResolvers) {
}

/**
 * {@inheritDoc}
 * <p>This implementation returns {@code null}.
 */
@Override
@Nullable
public Validator getValidator() {
    return null;
}

/**
 * {@inheritDoc}
 * <p>This implementation returns {@code null}.
 */
@Override
@Nullable
public MessageCodesResolver getMessageCodesResolver() {
    return null;
}

}

WebMvcConfigurerAdapter是一個典型的適配器,這個抽象類中沒有抽象方法,全部的方法都是對接口的一個空實現,這樣的好處是用戶類就只須要繼承適配器類，只實現感興趣的方法就好了。

springboot 2.0中這個抽象類已通過時,咱們能夠直接實現WebMvcConfigurer接口,2.0使用了java8的特性 default 方法。
[Java] 純文本查看 複製代碼
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public interface WebMvcConfigurer {

/**
 * Helps with configuring HandlerMappings path matching options such as trailing slash match,
 * suffix registration, path matcher and path helper.
 * Configured path matcher and path helper instances are shared for:
 * <ul>
 * <li>RequestMappings</li>
 * <li>ViewControllerMappings</li>
 * <li>ResourcesMappings</li>
 * </ul>
 * @since 4.0.3
 */
default void configurePathMatch(PathMatchConfigurer configurer) {
}

/**
 * Configure content negotiation options.
 */
default void configureContentNegotiation(ContentNegotiationConfigurer configurer) {
}

/**
 * Configure asynchronous request handling options.
 */
default void configureAsyncSupport(AsyncSupportConfigurer configurer) {
}

/**
 * Configure a handler to delegate unhandled requests by forwarding to the
 * Servlet container's "default" servlet. A common use case for this is when
 * the {@link DispatcherServlet} is mapped to "/" thus overriding the
 * Servlet container's default handling of static resources.
 */
default void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
}

/**
 * Add {@link Converter}s and {@link Formatter}s in addition to the ones
 * registered by default.
 */
default void addFormatters(FormatterRegistry registry) {
}

/**
 * Add Spring MVC lifecycle interceptors for pre- and post-processing of
 * controller method invocations. Interceptors can be registered to apply
 * to all requests or be limited to a subset of URL patterns.
 * <p><strong>Note</strong> that interceptors registered here only apply to
 * controllers and not to resource handler requests. To intercept requests for
 * static resources either declare a
 * {@link org.springframework.web.servlet.handler.MappedInterceptor MappedInterceptor}
 * bean or switch to advanced configuration mode by extending
 * {@link org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport
 * WebMvcConfigurationSupport} and then override {@code resourceHandlerMapping}.
 */
default void addInterceptors(InterceptorRegistry registry) {
}

/**
 * Add handlers to serve static resources such as images, js, and, css
 * files from specific locations under web application root, the classpath,
 * and others.
 */
default void addResourceHandlers(ResourceHandlerRegistry registry) {
}

/**
 * Configure cross origin requests processing.
 * @since 4.2
 */
default void addCorsMappings(CorsRegistry registry) {
}

/**
 * Configure simple automated controllers pre-configured with the response
 * status code and/or a view to render the response body. This is useful in
 * cases where there is no need for custom controller logic -- e.g. render a
 * home page, perform simple site URL redirects, return a 404 status with
 * HTML content, a 204 with no content, and more.
 */
default void addViewControllers(ViewControllerRegistry registry) {
}

/**
 * Configure view resolvers to translate String-based view names returned from
 * controllers into concrete {@link org.springframework.web.servlet.View}
 * implementations to perform rendering with.
 * @since 4.1
 */
default void configureViewResolvers(ViewResolverRegistry registry) {
}

/**
 * Add resolvers to support custom controller method argument types.
 * <p>This does not override the built-in support for resolving handler
 * method arguments. To customize the built-in support for argument
 * resolution, configure {@link RequestMappingHandlerAdapter} directly.
 * @param resolvers initially an empty list
 */
default void addArgumentResolvers(List<HandlerMethodArgumentResolver> resolvers) {
}

/**
 * Add handlers to support custom controller method return value types.
 * <p>Using this option does not override the built-in support for handling
 * return values. To customize the built-in support for handling return
 * values, configure RequestMappingHandlerAdapter directly.
 * @param handlers initially an empty list
 */
default void addReturnValueHandlers(List<HandlerMethodReturnValueHandler> handlers) {
}

/**
 * Configure the {@link HttpMessageConverter}s to use for reading or writing
 * to the body of the request or response. If no converters are added, a
 * default list of converters is registered.
 * <p><strong>Note</strong> that adding converters to the list, turns off
 * default converter registration. To simply add a converter without impacting
 * default registration, consider using the method
 * {@link #extendMessageConverters(java.util.List)} instead.
 * @param converters initially an empty list of converters
 */
default void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
}

/**
 * A hook for extending or modifying the list of converters after it has been
 * configured. This may be useful for example to allow default converters to
 * be registered and then insert a custom converter through this method.
 * @param converters the list of configured converters to extend.
 * @since 4.1.3
 */
default void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
}

/**
 * Configure exception resolvers.
 * <p>The given list starts out empty. If it is left empty, the framework
 * configures a default set of resolvers, see
 * {@link WebMvcConfigurationSupport#addDefaultHandlerExceptionResolvers(List)}.
 * Or if any exception resolvers are added to the list, then the application
 * effectively takes over and must provide, fully initialized, exception
 * resolvers.
 * <p>Alternatively you can use
 * {@link #extendHandlerExceptionResolvers(List)} which allows you to extend
 * or modify the list of exception resolvers configured by default.
 * @param resolvers initially an empty list
 * @see #extendHandlerExceptionResolvers(List)
 * @see WebMvcConfigurationSupport#addDefaultHandlerExceptionResolvers(List)
 */
default void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> resolvers) {
}

/**
 * Extending or modify the list of exception resolvers configured by default.
 * This can be useful for inserting a custom exception resolver without
 * interfering with default ones.
 * @param resolvers the list of configured resolvers to extend
 * @since 4.3
 * @see WebMvcConfigurationSupport#addDefaultHandlerExceptionResolvers(List)
 */
default void extendHandlerExceptionResolvers(List<HandlerExceptionResolver> resolvers) {
}

/**
 * Provide a custom {@link Validator} instead of the one created by default.
 * The default implementation, assuming JSR-303 is on the classpath, is:
 * {@link org.springframework.validation.beanvalidation.OptionalValidatorFactoryBean}.
 * Leave the return value as {@code null} to keep the default.
 */
@Nullable
default Validator getValidator() {
    return null;
}

/**
 * Provide a custom {@link MessageCodesResolver} for building message codes
 * from data binding and validation error codes. Leave the return value as
 * {@code null} to keep the default.
 */
@Nullable
default MessageCodesResolver getMessageCodesResolver() {
    return null;
}

}

2.0 中也能夠使用WebMvcConfigurationSupport但這樣會使自動配置失效,須要從新配置後才能夠有效

[Java] 純文本查看 複製代碼
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@Override

protected void addResourceHandlers(ResourceHandlerRegistry registry) {

    registry.addResourceHandler("/static/**").addResourceLocations("classpath:/static/");

    super.addResourceHandlers(registry);

}

綜上2.0中實現WebMvcConfigure接口,配置攔截器是最合適的