Java for Web学习笔记（三八）：自定义tag（6）一些注意

引入的base.jspf

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@ page import="cn.wei.flowingflying.customer_support.Ticket,cn.wei.flowingflying.customer_support.Attachment" %> <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %> <%@ taglib prefix="wrox" uri="http://www.wrox.com/jsp/tld/wrox" %> <%@ taglib prefix="template" tagdir="/WEB-INF/tags/template" %>

会报错：

org.apache.jasper.JasperException: /WEB-INF/tags/template/loggedOut.tag (line: 4, column: 1) /WEB-INF/jsp/base.jspf (line: 1, column: 9) <%@ page directive cannot be used in a tag file

需要修订为

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %> <%@ taglib prefix="wrox" uri="http://www.wrox.com/jsp/tld/wrox" %> <%@ taglib prefix="template" tagdir="/WEB-INF/tags/template" %>

在jsp的注释中，尽可能不要写入<>

<!-- At this point the attribute is specified within the tag body content, so to specify the real tag body content you need to use the <jsp:body> tag. --> 会报错： org.apache.jasper.JasperException: /WEB-INF/tags/template/loggedOut.tag (line: 10, column: 1) Must use jsp:body to specify tag body for <template:main if jsp:attribute is used. 改为： <!-- At this point the attribute is specified within the tag body content, so to specify the real tag body content you need to use the jsp:body tag. -->

jsp:attribute和jsp:body之间不要加入注释

<template:main htmlTitle="${htmlTitle}" bodyTitle="${bodyTitle}"> <jsp:attribute name="headContent"> <link rel="stylesheet" href="<c:url value="/resource/stylesheet/login.css" />" /> </jsp:attribute> <jsp:attribute name="navigationContent" /> <!-- At this point the attribute is specified within the tag body content, so to specify the real tag body content you need to use the jsp:body tag. --> <jsp:body> <jsp:doBody /> </jsp:body> </template:main> 这会报错： 十一月 30, 2016 9:07:18 上午 org.apache.catalina.core.ApplicationDispatcher invoke 严重: Servlet.service() for servlet jsp threw exception org.apache.jasper.JasperException: /WEB-INF/tags/template/loggedOut.tag (line: 10, column: 1) Must use jsp:body to specify tag body for <template:main if jsp:attribute is used. at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:41) at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:275) at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:91) at org.apache.jasper.compiler.Parser.parseJspAttributeAndBody(Parser.java:1044) at org.apache.jasper.compiler.Parser.parseOptionalBody(Parser.java:1004) at org.apache.jasper.compiler.Parser.parseCustomTag(Parser.java:1281) at org.apache.jasper.compiler.Parser.parseElements(Parser.java:1460) at org.apache.jasper.compiler.Parser.parse(Parser.java:139) at org.apache.jasper.compiler.ParserController.doParse(ParserController.java:227) at org.apache.jasper.compiler.ParserController.parse(ParserController.java:100) at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:199) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:356) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:336) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:323) at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:585) at org.apache.jasper.servlet.JspServletWrapper.loadTagFile(JspServletWrapper.java:246) at org.apache.jasper.compiler.TagFileProcessor.loadTagFile(TagFileProcessor.java:587) at org.apache.jasper.compiler.TagFileProcessor.access$000(TagFileProcessor.java:50) at org.apache.jasper.compiler.TagFileProcessor$TagFileLoaderVisitor.visit(TagFileProcessor.java:674) at org.apache.jasper.compiler.Node$CustomTag.accept(Node.java:1536) at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2376) at org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2428) at org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2434) at org.apache.jasper.compiler.Node$Root.accept(Node.java:464) at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2376) at org.apache.jasper.compiler.TagFileProcessor.loadTagFiles(TagFileProcessor.java:692) at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:229) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:356) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:336) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:323) at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:585) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:363) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:396) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:340) at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:720) at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:466) at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:391) at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:318) at cn.wei.flowingflying.customer_support.LoginServlet.doGet(LoginServlet.java:55) at javax.servlet.http.HttpServlet.service(HttpServlet.java:622) at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:528) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1099) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:670) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1520) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1476) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Unknown Source)

相关链接： 我的Professional Java for Web Applications相关文章