我正在使用 Netbeans 7 IDE、Glassfish 3+ 服务器、servlet 类和会话 bean编写此页面上的 Netbeans Affable 教程。servlet 类应该调用 index.jsp 类。
但是每当我在 Netbeans 中运行该项目时，都会出现错误。
这是 index.jsp 页面。
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@taglib prefix="sql" uri="http://java.sun.com/jsp/jstl/sql"%>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<link rel="stylesheet" type="text/css" href="css/affablebean.css">
<title>The Affable Bean</title>
</head>
<body>
<div id="indexLeftColumn">
<div id="welcomeText">
<p style="font-size: larger">Welcome to the online home of the Affable Bean Green Grocer.</p>
<p>Enjoy browsing and learning more about our unique home delivery
service bringing you fresh organic produce, dairy, meats, breads
and other delicious and healthy items to your doorstep.</p>
</div>
</div>
<div id="indexRightColumn">
<c:forEach var="category" items="${categories}">
<div class="categoryBox">
<a href="category?${category.id}">
<span class="categoryLabel"></span>
<span class="categoryLabelText">${category.name}</span>
<img src="${initParam.categoryImagePath}${category.name}.jpg"
alt="${category.name}" class="categoryImage">
</a>
</div>
</c:forEach>
</div>
</body>
</html>
你好是来自 glassfish 3+ 服务器的错误消息
WARNING: StandardWrapperValve[jsp]: PWC1406: Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: /index.jsp(9,0) PWC5988: Page directive: illegal to have multiple occurrences of 'contentType' with different values (old: text/html; charset=UTF-8, new: text/html)
at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:81)
at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:376)
at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:204)
at org.apache.jasper.compiler.Validator$DirectiveVisitor.visit(Validator.java:173)
at org.apache.jasper.compiler.Node$PageDirective.accept(Node.java:600)
at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2297)
at org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2347)
at org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2353)
at org.apache.jasper.compiler.Node$Root.accept(Node.java:499)
at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2297)
at org.apache.jasper.compiler.Validator.validate(Validator.java:1826)
at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:223)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:451)
at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:625)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:375)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:473)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:377)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:770)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1550)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:331)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
at com.sun.enterprise.v3.services.impl.ContainerMapper$AdapterCallable.call(ContainerMapper.java:317)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:860)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:757)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1056)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:229)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:722)
WARNING: StandardWrapperValve[jsp]: PWC1406: Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: /index.jsp(9,0) PWC5988: Page directive: illegal to have multiple occurrences of 'contentType' with different values (old: text/html; charset=UTF-8, new: text/html)
at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:81)
at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:376)
at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:204)
at org.apache.jasper.compiler.Validator$DirectiveVisitor.visit(Validator.java:173)
at org.apache.jasper.compiler.Node$PageDirective.accept(Node.java:600)
at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2297)
at org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2347)
at org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2353)
at org.apache.jasper.compiler.Node$Root.accept(Node.java:499)
at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2297)
at org.apache.jasper.compiler.Validator.validate(Validator.java:1826)
at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:223)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:451)
at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:625)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:375)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:473)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:377)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:770)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1550)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:331)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
at com.sun.enterprise.v3.services.impl.ContainerMapper$AdapterCallable.call(ContainerMapper.java:317)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:860)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:757)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1056)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:229)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:722)
WARNING: StandardWrapperValve[jsp]: PWC1406: Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: /index.jsp(9,0) PWC5988: Page directive: illegal to have multiple occurrences of 'contentType' with different values (old: text/html; charset=UTF-8, new: text/html)
at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:81)
at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:376)
at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:204)
at org.apache.jasper.compiler.Validator$DirectiveVisitor.visit(Validator.java:173)
at org.apache.jasper.compiler.Node$PageDirective.accept(Node.java:600)
at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2297)
at org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2347)
at org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2353)
at org.apache.jasper.compiler.Node$Root.accept(Node.java:499)
at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2297)
at org.apache.jasper.compiler.Validator.validate(Validator.java:1826)
at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:223)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:451)
at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:625)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:375)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:473)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:377)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:770)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1550)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:331)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
at com.sun.enterprise.v3.services.impl.ContainerMapper$AdapterCallable.call(ContainerMapper.java:317)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:860)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:757)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1056)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:229)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:722)
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