问题
I am converting a JSP/Servlet dynamic web project to Struts 2 and the custom error pages (that previously worked with the JSP/Servlet version) have stopped working.
When I induce a 404 error by accessing a non-existent page like abc.jsp, it throws below exception:
SEVERE: Servlet.service() for servlet jsp threw exception
The Struts dispatcher cannot be found. This is usually caused by using Struts tags without the associated filter. Struts tags are only usable when the request has passed through its servlet filter, which initializes the Struts dispatcher needed for this tag. - [unknown location]
at org.apache.struts2.views.jsp.TagUtils.getStack(TagUtils.java:60)
at org.apache.struts2.views.jsp.StrutsBodyTagSupport.getStack(StrutsBodyTagSupport.java:44)
at org.apache.struts2.views.jsp.ComponentTagSupport.doStartTag(ComponentTagSupport.java:48)
at org.apache.jsp._404_jsp._jspx_meth_s_005finclude_005f0(_404_jsp.java:111)
at org.apache.jsp._404_jsp._jspService(_404_jsp.java:71)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:748)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:488)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:411)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:338)
at org.apache.catalina.core.StandardHostValve.custom(StandardHostValve.java:467)
at org.apache.catalina.core.StandardHostValve.status(StandardHostValve.java:338)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:203)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Nov 18, 2014 11:14:56 PM org.apache.catalina.core.StandardHostValve custom
SEVERE: Exception Processing ErrorPage[errorCode=404, location=/404.jsp]
org.apache.jasper.JasperException: An exception occurred processing JSP page /404.jsp at line 6
3: <html>
4: <head>
5: <title>My Site - WHOOPS!</title>
6: <s:include value="css/style2.css" />
7: </head>
8:
9: <body class="errorpage">
Stacktrace:
at org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:568)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:470)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:748)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:488)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:411)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:338)
at org.apache.catalina.core.StandardHostValve.custom(StandardHostValve.java:467)
at org.apache.catalina.core.StandardHostValve.status(StandardHostValve.java:338)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:203)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Caused by: The Struts dispatcher cannot be found. This is usually caused by using Struts tags without the associated filter. Struts tags are only usable when the request has passed through its servlet filter, which initializes the Struts dispatcher needed for this tag. - [unknown location]
at org.apache.struts2.views.jsp.TagUtils.getStack(TagUtils.java:60)
at org.apache.struts2.views.jsp.StrutsBodyTagSupport.getStack(StrutsBodyTagSupport.java:44)
at org.apache.struts2.views.jsp.ComponentTagSupport.doStartTag(ComponentTagSupport.java:48)
at org.apache.jsp._404_jsp._jspx_meth_s_005finclude_005f0(_404_jsp.java:111)
at org.apache.jsp._404_jsp._jspService(_404_jsp.java:71)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
... 23 more
Below is my project structure:
web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
id="WebApp_ID" version="3.0">
<display-name>My Site</display-name>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<error-page>
<error-code>404</error-code>
<location>/404.jsp</location>
</error-page>
<error-page>
<error-code>500</error-code>
<location>/500.jsp</location>
</error-page>
...
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>
How do I make the custom error pages work with Struts 2?
回答1:
You are calling a JSP directly, and trying to use a Struts tag inside it:
6: <s:include value="css/style2.css" />
Turn this to plain html and it will work.
Otherwise, you need to call an action.
回答2:
Instead of custom error page create a custom error action that returns a result to a custom error page.
struts.xml:
<action name "error" class="ErrorAction">
<result name="404">/404.jsp</result>
<result name="500">/500.jsp</result>
</action>
ErrorAction:
public class ErrorAction extends ActionSupport {
private Integer statusCode;
//getter and setter
@Override
public String execute() {
if (stausCode != null)
switch (statusCode){
case 404:
return "404";
case 500:
return "500";
}
}
}
web.xml:
<error-page>
<error-code>404</error-code>
<location>/error_code.jsp</location>
</error-page>
<error-page>
<error-code>500</error-code>
<location>/error_code.jsp</location>
</error-page>
error_code.jsp:
<%
Integer statusCode = (Integer) request
.getAttribute("javax.servlet.error.status_code");
response.sendRedirect(pageContext.getServletContext().getContextPath()
+"/error?statusCode="+statusCode );
%>
来源：https://stackoverflow.com/questions/26998015/custom-404-error-page-not-working-with-struts-2