反射机制设置header

private void reflectSetHeader(HttpServletRequest request, String key, String value){
        Class<? extends HttpServletRequest> requestClass = request.getClass();
        try {
            Field requestField = requestClass.getDeclaredField("request");
            requestField.setAccessible(true);
            Object requestObj = requestField.get(request);
            Field coyoteRequestField = requestObj.getClass().getDeclaredField("coyoteRequest");
            coyoteRequestField.setAccessible(true);
            Object coyoteRequestObj = coyoteRequestField.get(requestObj);
            Field headersField = coyoteRequestObj.getClass().getDeclaredField("headers");
            headersField.setAccessible(true);
            MimeHeaders headersObj = (MimeHeaders)headersField.get(coyoteRequestObj);
            headersObj.removeHeader(key);
            headersObj.addValue(key).setString(value);
        } catch (Exception e) {
            logger.error("reflect set header {} error {}", key, e);
        }
    }

Filter中使用

@Component
@Slf4j
public class MyFilter extends OncePerFilter{

	@AutoWired
	private XxService xxService; 
	
	@Override
	protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
        String requestMethod = request.getMethod();
        // options 直接放行
        if (requestMethod.equals(HttpMethod.OPTIONS.name())) {
            filterChain.doFilter(request, response);
        }
        reflectSetHeader(request, "X-xx", xxService.getXx());
        filterChain.doFilter(request, response);
    }
    
    private void reflectSetHeader(HttpServletRequest request, String key, String value){
        Class<? extends HttpServletRequest> requestClass = request.getClass();
        try {
            Field requestField = requestClass.getDeclaredField("request");
            requestField.setAccessible(true);
            Object requestObj = requestField.get(request);
            Field coyoteRequestField = requestObj.getClass().getDeclaredField("coyoteRequest");
            coyoteRequestField.setAccessible(true);
            Object coyoteRequestObj = coyoteRequestField.get(requestObj);
            Field headersField = coyoteRequestObj.getClass().getDeclaredField("headers");
            headersField.setAccessible(true);
            MimeHeaders headersObj = (MimeHeaders)headersField.get(coyoteRequestObj);
            headersObj.removeHeader(key);
            headersObj.addValue(key).setString(value);
        } catch (Exception e) {
            logger.error("reflect set header {} error {}", key, e);
        }
    }

	// 供外部调用，获取xx 
    public static String getXxFromHeaders(){
        HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes()).getRequest();
        return request.getHeader("X-xx");

    }
}

Interceptor使用

@Slf4j
public class MyInterceptor implements HandlerInterceptor {

	@AutoWired
	private XxService xxService; 

	@Override
    public boolean preHandle(HttpServletRequest httpServletRequest,
                             HttpServletResponse httpServletResponse, Object handler) throws Exception {
        String requestMethod = httpServletRequest.getMethod();
        // options 直接放行
        if (requestMethod.equals(HttpMethod.OPTIONS.name())) {
            return true;
        }
        reflectSetHeader(request, "X-xx", xxService.getXx());
        filterChain.doFilter(request, response);
        return true;
    }
    
    private void reflectSetHeader(HttpServletRequest request, String key, String value){
        Class<? extends HttpServletRequest> requestClass = request.getClass();
        try {
            Field requestField = requestClass.getDeclaredField("request");
            requestField.setAccessible(true);
            Object requestObj = requestField.get(request);
            Field coyoteRequestField = requestObj.getClass().getDeclaredField("coyoteRequest");
            coyoteRequestField.setAccessible(true);
            Object coyoteRequestObj = coyoteRequestField.get(requestObj);
            Field headersField = coyoteRequestObj.getClass().getDeclaredField("headers");
            headersField.setAccessible(true);
            MimeHeaders headersObj = (MimeHeaders)headersField.get(coyoteRequestObj);
            headersObj.removeHeader(key);
            headersObj.addValue(key).setString(value);
        } catch (Exception e) {
            logger.error("reflect set header {} error {}", key, e);
        }
    }

	// 供外部调用，获取xx 
    public static String getXxFromHeaders(){
        HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes()).getRequest();
        return request.getHeader("X-xx");

    }
}

• 拦截器需要手动配置

@Configuration
public class InterceptorConfig implements WebMvcConfigurer {

	// 若要在Interceptor中进行依赖注入，则需要将拦截器注册为一个 Bean
    @Bean
    public MyInterceptor myInterceptor() {
        return new MyInterceptor ();
    }
    
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(myInterceptor()).addPathPatterns("/**");
    }
}