Question

当我在登录页面时，我收到了一个ViewExpiredException，它不应该是。所以我在过滤器上读了一篇文章（由BalusC推荐）。可能是页面是从浏览器的缓存加载而不是从服务器加载。所以我已经实现了这段代码

@WebFilter(servletNames={"Faces Servlet"})
public class NoCacheFilter implements Filter {

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest httpReq = (HttpServletRequest) request;
        HttpServletResponse httpRes = (HttpServletResponse) response;

        if (!httpReq.getRequestURI().startsWith(httpReq.getContextPath() + ResourceHandler.RESOURCE_IDENTIFIER)) { // Skip JSF resources (CSS/JS/Images/etc)
            httpRes.setHeader("Cache-Control", "no-cache, no-store, must-revalidate"); // HTTP 1.1.
            httpRes.setHeader("Pragma", "no-cache"); // HTTP 1.0.
            httpRes.setDateHeader("Expires", 0); // Proxies.
        }

        chain.doFilter(request, response);
    }

    // ...

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        throw new UnsupportedOperationException("Not supported yet.");
    }

    @Override
    public void destroy() {
        throw new UnsupportedOperationException("Not supported yet.");
    }
}

但是当我尝试测试时，我收到以下错误：

The module has not been deployed.
    at org.netbeans.modules.j2ee.deployment.devmodules.api.Deployment.deploy(Deployment.java:210)
    at org.netbeans.modules.j2ee.ant.Deploy.execute(Deploy.java:106)
    at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:291)
    at sun.reflect.GeneratedMethodAccessor193.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:601)
    at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
    at org.apache.tools.ant.Task.perform(Task.java:348)
    at org.apache.tools.ant.Target.execute(Target.java:390)
    at org.apache.tools.ant.Target.performTasks(Target.java:411)
    at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1399)
    at org.apache.tools.ant.Project.executeTarget(Project.java:1368)
    at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:41)
    at org.apache.tools.ant.Project.executeTargets(Project.java:1251)
    at org.apache.tools.ant.module.bridge.impl.BridgeImpl.run(BridgeImpl.java:284)
    at org.apache.tools.ant.module.run.TargetExecutor.run(TargetExecutor.java:539)
    at org.netbeans.core.execution.RunClassThread.run(RunClassThread.java:153)

Answer 1

您在过滤器初始化（和销毁）期间抛出异常。因此，过滤器的初始化将完全失败并导致webapp的启动被阻止。删除这些行。你不应该故意在那里抛出异常。

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

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

阅读过滤器的javadoc，了解这些方法的用途。

另见：

Our Servlet-Filters tag wiki page

禁用浏览器缓存JSF

1 个答案:

另见：