[求助]帮我分一下问题在那里？
我在书上抄了一个easy.jsp源代码: <%@ page contentType="text/html" %> <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <html> <head> <title>JSP is Easy</title> </head> <body bgcolor="white">
<h1>JSP is as easy as ...</h1>
<%-- Calculate the sum of 1 + 2 + 3 dynamically --%> 1 + 2 + 3 = <c:out value="${1 + 2 + 3}" />
</body> </html> 可是为什么运行的时候为什么出现这样的错误提示：
A Servlet Exception Has Occurred
org.apache.jasper.JasperException: This absolute uri (http://java.sun.com/jsp/jstl/core) cannot be resolved in either web.xml or the jar files deployed with this application at org.apache.jasper.compiler.TagLibraryInfoImpl.(TagLibraryInfoImpl.java:194) at org.apache.jasper.compiler.TagLibraryInfoImpl. (TagLibraryInfoImpl.java:174) at org.apache.jasper.compiler.JspParseEventListener.processTaglibDirective(JspParseEventListener.java:1148) at org.apache.jasper.compiler.JspParseEventListener.handleDirective(JspParseEventListener.java:755) at org.apache.jasper.compiler.DelegatingListener.handleDirective(DelegatingListener.java:121) at org.apache.jasper.compiler.Parser$Directive.accept(Parser.java:243) at org.apache.jasper.compiler.Parser.parse(Parser.java:1132) at org.apache.jasper.compiler.Parser.parse(Parser.java:1091) at org.apache.jasper.compiler.Parser.parse(Parser.java:1087) at org.apache.jasper.compiler.ParserController.parse(ParserController.java:213) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:210) at org.apache.jasper.servlet.JspServlet.loadJSP(JspServlet.java:543) at org.apache.jasper.servlet.JspServlet$JspServletWrapper.loadIfNecessary(JspServlet.java:176) at org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:188) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:381) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:473) at javax.servlet.http.HttpServlet.service(HttpServlet.java:1264) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:215) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943) at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2366) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:462) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:163) at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943) at org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:1005) at org.apache.catalina.connector.http.HttpProcessor.run(HttpProcessor.java:1098) at java.lang.Thread.run(Unknown Source)
