偶在页面里引入了标签如下：
<%@ taglib prefix="c" uri="http://java.sun.com/jstl/core" %>
出错提示：
org.apache.jasper.JasperException: /index.jsp(0,0) This absolute uri (http://java.sun.com/jstl/core) cannot be resolved in either web.xml or the jar files deployed with this application
at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:94)
at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:428)
at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:126)
at org.apache.jasper.compiler.Parser.processIncludeDirective(Parser.java:307)
at org.apache.jasper.compiler.Parser.parseIncludeDirective(Parser.java:340)
at org.apache.jasper.compiler.Parser.parseDirective(Parser.java:378)
at org.apache.jasper.compiler.Parser.parseElements(Parser.java:795)
at org.apache.jasper.compiler.Parser.parse(Parser.java:122)
at org.apache.jasper.compiler.ParserController.parse(ParserController.java:199)
at org.apache.jasper.compiler.ParserController.parse(ParserController.java:153)
at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:227)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:369)
at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:473)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:190)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
对于JAVAEE5.0及以上版本，使用的是jstl1.2.jar的版本，很简单，只需要将jstl1.2.jar拷贝到Tomcat安装目录下的lib下即可。
对于jstl1.1.jar的话，则需要在web.xml中增加taglib，引入对tld文件，还要加上standard.jar。