单病种质量管理意义:我是jsp的初学者,想做一个JSP的聊天系统

我用的是jcreator,jsdk搭配tomcat5.0,
我想请教大家的是,比如我用jcreator编好了一个文件leavechat.jsp把它放置在tomcat/webapps/目录下,然后用浏览起打开http://localhost:8080/leavechat.jsp,为什么会出现下面的问题:
type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: /leavechat.jsp(15,2) Unterminated <% tag
org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:83)
org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:402)
org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:170)
org.apache.jasper.compiler.Parser.parseScriptlet(Parser.java:836)
org.apache.jasper.compiler.Parser.parseElements(Parser.java:1589)
org.apache.jasper.compiler.Parser.parse(Parser.java:171)
org.apache.jasper.compiler.ParserController.parse(ParserController.java:247)
org.apache.jasper.compiler.ParserController.parse(ParserController.java:149)
org.apache.jasper.compiler.ParserController.parse(ParserController.java:135)
org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:237)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:456)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:439)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:552)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:291)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)

note The full stack trace of the root cause is available in the Tomcat logs.

请大家能给予帮助,谢谢!