jsp - 为什么 JSP 2.0 自定义标记文件不能与 Portlet 一起使用？

Question

我正在尝试在我的 liferay 6.0 portlet 应用程序中使用 JSP 2.0 标记文件。

以下是我遵循的步骤：

1. 我的jsp很简单：home.jsp.

   <%@ taglib prefix="tags" tagdir="/WEB-INF/tags" %>
   <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
   
   <table>
       <tr>
           <td> <tags:tagDemo/> </td>
           <td><c:out value="Cout Hello"/></td>
       </tr>
   </table>
   

2. 我的标签文件非常简单：/WEB-INF/tags/tagDemo.tag

   hello
   

3. /WEB-INF/web.xml

   <?xml version="1.0" encoding="UTF-8"?>
   
   <web-app xmlns="http://java.sun.com/xml/ns/j2ee"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-  app_2_4.xsd" version="2.4">
   
       <context-param>
           <param-name>log4jConfigLocation</param-name>
           <param-value>/WEB-INF/classes/log4j.properties</param-value>
       </context-param>
   
       <servlet>
           <servlet-name>view-servlet</servlet-name>
           <servlet-class>org.springframework.web.servlet.ViewRendererServlet</servlet-class>
           <load-on-startup>1</load-on-startup>
       </servlet>
   
       <servlet-mapping>
           <servlet-name>view-servlet</servlet-name>
           <url-pattern>/WEB-INF/servlet/view</url-pattern>
       </servlet-mapping>
   
   </web-app>
   

这会引发以下错误：

00:14:42,642 ERROR [render_portlet_jsp:154] org.apache.jasper.JasperException: /WEB-INF/jsp/home.jsp (line: 55, column: 6) No tag "tagDemo" defined in tag library imported with prefix "tags"
    at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:42)
    at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:408)
    at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:199)
    at org.apache.jasper.compiler.Parser.parseCustomTag(Parser.java:1215)
    at org.apache.jasper.compiler.Parser.parseElements(Parser.java:1450)
    at org.apache.jasper.compiler.Parser.parse(Parser.java:138)
    at org.apache.jasper.compiler.ParserController.doParse(ParserController.java:242)
    at org.apache.jasper.compiler.ParserController.parse(ParserController.java:102)
    at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:198)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:373)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:353)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:340)
    at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:646)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:357)
    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:722)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:72)

谁能告诉我问题出在哪里？

Answer 1

我认为这个指令中的错误是：<%@ taglib prefix="tags" tagdir="/WEB-INF/tags" %>

它应该是：<%@ taglib prefix="tags" tagdir="/WEB-INF/tags/tagDemo.tag" %>

我还在这里找到了 JSP 2.0 自定义标签的好教程。