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我正在尝试从 JBoss 7.1.1 上的 Java EE 5 教程中部署 Duke's Bank 示例。我只使用（未更改）源代码和用于部署的标准 XML 配置文件，这里的部分练习是看看我如何构建我自己的基于 JSP 的项目。

我得到的异常如下：

  ERROR [[jsp]] Servlet.service() for servlet jsp threw exception: java.lang.NullPointerException
    at javax.faces.webapp.UIComponentClassicTagBase.setJspId(UIComponentClassicTagBase.java:1858) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at org.apache.jsp.main_jsp._jspx_meth_f_005fview_005f0(main_jsp.java:99)
    at org.apache.jsp.main_jsp._jspService(main_jsp.java:76)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) [jbossweb-7.0.13.Final.jar:]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) [jboss-servlet-api_3.0_spec-1.0.0.Final.jar:1.0.0.Final]
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:369) [jbossweb-7.0.13.Final.jar:]
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:326) [jbossweb-7.0.13.Final.jar:]
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:253) [jbossweb-7.0.13.Final.jar:]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) [jboss-servlet-api_3.0_spec-1.0.0.Final.jar:1.0.0.Final]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:397) [jbossweb-7.0.13.Final.jar:]
    at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.1.1.Final.jar:7.1.1.Final]
    at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153) [jboss-as-web-7.1.1.Final.jar:7.1.1.Final]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368) [jbossweb-7.0.13.Final.jar:]
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [jbossweb-7.0.13.Final.jar:]
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:671) [jbossweb-7.0.13.Final.jar:]
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:930) [jbossweb-7.0.13.Final.jar:]
    at java.lang.Thread.run(Thread.java:636) [rt.jar:1.6.0_18]

我没有给出任何 JBoss 配置文件，WAR 的 WEB-INF 部分如下所示：

$ jar tvf build/lib/dukebank-web.war 
     0 Sat Dec 15 22:00:12 GMT 2012 META-INF/
   123 Sat Dec 15 22:00:10 GMT 2012 META-INF/MANIFEST.MF
     0 Sat Dec 15 22:00:12 GMT 2012 WEB-INF/
  2514 Fri Dec 14 14:29:20 GMT 2012 WEB-INF/web.xml
  1348 Sat Dec 15 08:19:46 GMT 2012 WEB-INF/dukesBank.tld
  7245 Sat Dec 15 08:19:46 GMT 2012 WEB-INF/faces-config.xml
  2153 Sat Dec 15 08:19:46 GMT 2012 WEB-INF/tutorial-template.tld
     0 Sat Dec 15 22:00:12 GMT 2012 WEB-INF/classes/...

导致此问题的 JSP 文件 (main.jsp) 是：

<f:view>
    <h:form>
        <jsp:include page="/template/template.jsp"/>
        <center>
            <h3><h:outputText value="#{bundle.Welcome}"/></h3>
        </center>
    </h:form>
</f:view>

它包括的模板文件：

<%@ taglib uri="/WEB-INF/tutorial-template.tld" prefix="tt" %>
<%@ page errorPage="/template/errorpage.jsp" %>
<%@ include file="/template/screendefinitions.jspf" %>
<html>
<head>
<title>
  <tt:insert definition="bank" parameter="title"/>
</title>
<link rel="stylesheet" type="text/css" href="stylesheet.css">
</head>
<body bgcolor="#ffffff">
  <tt:insert definition="bank" parameter="banner"/>
  <tt:insert definition="bank" parameter="links"/>
</body>
</html>

我将不再处理任何文件，因为正如我在开始时所说的那样，我没有更改任何我使用过的文件。

非常感谢您的帮助，史蒂夫

4

1 回答 1

2

The Duke's Bank example is based on JSF, which is a component based MVC framework which previously used to use JSP as "View". JSF pages are supposed to be opened by an URL which matches the <url-pattern> of the FacesServlet as definied in webapp's web.xml. For example, if it's *.jsf, then you should open it by main.jsf instead of main.jsp. Or if it's /faces/*, then you should open it by faces/main.jsp instead of main.jsp. This would invoke the FacesServlet which in turn will create the FacesContext and do all the JSF works.

You're getting a NPE on that line because the <f:view> (which is represented by the line at org.apache.jsp.main_jsp._jspx_meth_f_005fview_005f0(main_jsp.java:99) in the stack trace) is trying to find JSF's FacesContext, but can't seem to find one. This is true, since the FacesContext is supposed to be created by the FacesServlet.

See also:

Unrelated to the concrete problem: the legacy Java EE 5 tutorial is not the right tutorial to read for JBoss 7. JBoss 7 is a modern Java EE 6 compatible container. Since Java EE 6, JSP is deprecated as JSF view technology and succeeded by Facelets. Also, JSF 1.x (part of Java EE 5) is really not what you would like to use these days, you should be heading to JSF 2.x (part of Java EE 6).

于 2012-12-16T10:54:55.473 回答