Question

我正在将JSP / Servlet动态Web项目转换为Struts 2，并且自定义错误页面（之前使用JSP / Servlet版本）已停止工作。

当我通过访问不存在的页面abc.jsp来引发404错误时，它会抛出异常：

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

以下是我的项目结构：

customerror

的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>

如何使自定义错误页面与Struts 2一起使用？

Answer 1

您正在直接调用JSP，并尝试在其中使用Struts标记：

6: <s:include value="css/style2.css" />

将其转换为纯HTML，它会起作用。

否则，您需要调用一个动作。

Answer 2

而不是自定义错误页面创建自定义错误操作，该操作将结果返回到自定义错误页面。

<强> struts.xml

<action name "error" class="ErrorAction">
  <result name="404">/404.jsp</result>
  <result name="500">/500.jsp</result>
</action>

<强> 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";
    }
  }
}

<强> 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>

<强> error_code.jsp

<% 
 Integer statusCode = (Integer) request
                       .getAttribute("javax.servlet.error.status_code");

 response.sendRedirect(pageContext.getServletContext().getContextPath()
                       +"/error?statusCode="+statusCode ); 
%>

自定义404错误页面不适用于Struts 2

2 个答案: