java.lang.IllegalStateException: No FacesContext is available to process this request的另一种处理方法

在JSF的运行环境中，往往会报如下的异常：

java.lang.IllegalStateException: No FacesContext is available to process this request. This is most likely due to the request being sent to the wrong path.

at com.sun.faces.taglib.jsf_core.ViewTag.doStartTag(ViewTag.java:159)

at org.apache.jsp.login_jsp._jspx_meth_f_005fview_005f0(login_jsp.java:112)

at org.apache.jsp.login_jsp._jspService(login_jsp.java:86)

at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)

at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)

at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)

at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)

at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646)

at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:438)

at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:374)

at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:302)

at org.apache.catalina.core.StandardHostValve.custom(StandardHostValve.java:421)

at org.apache.catalina.core.StandardHostValve.status(StandardHostValve.java:342)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:143)

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)

at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)

at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)

at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)

at java.lang.Thread.run(Thread.java:736)

在网上搜索的资料，基本都是集中在welcome-file-list的处理中，按照这些方法，还是得到异常。后来仔细看了一下异常，发现多了一些没注意到的问题：

SEVERE: Exception Processing ErrorPage[errorCode=404, location=/login.jsp]

在说明在Error Page的处理时，login.jsp的路径有问题。在web.xml中，修改如下：

<error-page>

<error-code>404</error-code>

<location>/faces/login.jsp</location> （或 <location>/login.faces</location>）

</error-page>

重启服务器，问题解决。