java - 拦截 Controller 请求的问题

Question

我想创建一个抽象 Controller ，它将根据扩展 Controller 的实际映射添加额外的请求映射。

例如，对于以下 Controller

@Controller
public class MyController extends VariableResolvingController {
    @RequestMapping("page.htm") 
    public void handlerMethod() {
    }
}

我希望它扩展 VariableResolvingController，它将使用“page.htm.context”URI 添加到其 resolveContextVariable(...) 方法的映射。

public abstract class VariableResolvingController {
    public final @ResponseBody Object resolveContextVariable(String variableName) {
        return "{}";
    }

    protected final void registerVariableResolver(String variableName, VariableResolver resolver) {
        //...
    }
}

这种方法增加了使用例如解析自定义变量的可能性。 AJAX 请求的方式对于客户端代码来说几乎是透明的。

您知道适合这种情况的现有解决方案吗？

解决方案:我通过编写自定义 HandlerMapping 实现了我的目标实现(本质上是 RequestMappingHandlerMapping 的装饰器)。

Answer 1

一种方法是将简单的 Servlet 过滤器添加到您的 spring mvc

 public class RequestCheckFilter implements Filter {

        @Override
        public void destroy() {
            // ...
        }

        @Override
        public void init(FilterConfig filterConfig) throws ServletException         {
            //
        }

        @Override
        public void doFilter(ServletRequest request,
                   ServletResponse response, FilterChain chain)
            throws IOException, ServletException {

            try {
                HttpServletRequest httpServletRequest = ((HttpServletRequest) request);
            String requestURI = httpServletRequest.getRequestURI();

            if (requestURI.endsWith(".context")) {
                request.getRequestDispatcher(requestURI.concat(".htm"))
                    .forward(request,response);
            } else {
                chain.doFilter(httpServletRequest, response);
            }
       } catch (Exception ex) {
            request.setAttribute("errorMessage", ex);
            request.getRequestDispatcher("/WEB-INF/views/jsp/error.jsp")
                           .forward(request, response);
       }

}

添加

public class MyWebInitializer extends
        AbstractAnnotationConfigDispatcherServletInitializer {

    //...

    @Override
    protected Filter[] getServletFilters() {
        return new Filter[]{new RequestCheckFilter()};
    }
}

或在 web.xml 中

<filter>
    <filter-name>reqHandlerFilter</filter-name>
    <filter-class>RequestCheckFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>reqHandlerFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>