1、今天，我在用c标签写一些样例，结果出现一些错误，写下作为记录

具体错误如下：

三月 31, 2014 9:46:28 下午 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet [jsp] in context with path [/HighCharts] threw exception [Unable to compile class for JSP: 

An error occurred at line: 25 in the jsp file: /JSP/forEach.jsp
List cannot be resolved to a type
22: 		<br />
23: 	</c:forEach>
24: 	<%
25: 			List<String> list = new ArrayList<String>();
26: 			list.add("You");
27: 			list.add("Hai");
28: 			list.add("Dong");

An error occurred at line: 25 in the jsp file: /JSP/forEach.jsp
ArrayList cannot be resolved to a type
22: 		<br />
23: 	</c:forEach>
24: 	<%
25: 			List<String> list = new ArrayList<String>();
26: 			list.add("You");
27: 			list.add("Hai");
28: 			list.add("Dong");

Stacktrace:] with root cause
org.apache.jasper.JasperException: Unable to compile class for JSP: 

An error occurred at line: 25 in the jsp file: /JSP/forEach.jsp
List cannot be resolved to a type
22: 		<br />
23: 	</c:forEach>
24: 	<%
25: 			List<String> list = new ArrayList<String>();
26: 			list.add("You");
27: 			list.add("Hai");
28: 			list.add("Dong");

An error occurred at line: 25 in the jsp file: /JSP/forEach.jsp
ArrayList cannot be resolved to a type
22: 		<br />
23: 	</c:forEach>
24: 	<%
25: 			List<String> list = new ArrayList<String>();
26: 			list.add("You");
27: 			list.add("Hai");
28: 			list.add("Dong");

Stacktrace:
	at org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:103)
	at org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:366)
	at org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:468)
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java:378)
	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:657)
	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:727)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:315)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
	at java.lang.Thread.run(Thread.java:722)

2、错误原因

由于List是Java中的集合，是java.util.*包中的，因为没有导入这个Java包，导致出现这个错误

3、解决办法

在JSP顶部添加下面这句

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>