最近在做Highcharts的过程中，在写js时，出现了以下异常：
严重: Servlet.service() for servlet jsp threw exception
org.apache.el.parser.ParseException: Encountered " ":" ": "" at line 1, column 10.
Was expecting one of:
"}" ...
"." ...
"[" ...
">" ...
"gt" ...
"<" ...
"lt" ...
">=" ...
"ge" ...
"<=" ...
"le" ...
"==" ...
"eq" ...
"!=" ...
"ne" ...
"&&" ...
"and" ...
"||" ...
"or" ...
"*" ...
"+" ...
"-" ...
"/" ...
"div" ...
"%" ...
"mod" ...
at org.apache.el.parser.ELParser.generateParseException(ELParser.java:2142)
at org.apache.el.parser.ELParser.jj_consume_token(ELParser.java:2024)
at org.apache.el.parser.ELParser.DynamicExpression(ELParser.java:147)
at org.apache.el.parser.ELParser.CompositeExpression(ELParser.java:43)
at org.apache.el.lang.ExpressionBuilder.createNodeInternal(ExpressionBuilder.java:114)
at org.apache.el.lang.ExpressionBuilder.build(ExpressionBuilder.java:172)
at org.apache.el.lang.ExpressionBuilder.createValueExpression(ExpressionBuilder.java:216)
at org.apache.el.ExpressionFactoryImpl.createValueExpression(ExpressionFactoryImpl.java:68)
at org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:937)
at org.apache.jsp.page.M5.M5006_jsp._jspService(M5006_jsp.java:514)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at com.kayak.web.user.filter.LoginCertifyFilter.doFilter(LoginCertifyFilter.java:123)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at com.kayak.web.base.filter.LocalRequestFilter.doFilter(LocalRequestFilter.java:27)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:745)
这是加载页面时报的错，按异常来看，应该跟el表达式脱不了干系。而注意到由该jsp页面生成的servlet类里报的错误行数（如红色部分所示）。在tomcat中打开该行，发现：
out.write((java.lang.String) org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate("${point.y:,.0f}", java.lang.String.class, (PageContext)_jspx_page_context, null, false));
会发现，跟$符号有关！其实，本意是在页面上直接显示$符号，表示美元符号，而并不想赋予它el表达式的含义。——这也是为啥我单独把该页面抽出来，不放在web环境，也就没经过tomcat。页面能正常显示的原因。
解决办法：加上转义符：
pointFormat: '{series.name}: \${point.y:,.0f}
'
其中\$即把$当成单纯的美元符使用。如果不转义，el的$根本无法解析point.y:,.0f ！！
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附：
1.为了不让charts显示导出的menu，
exporting: {
buttons:{
contextButton:{
enabled:false
}
}
}
如果直接这样写：exporting ： null 则会报错：can not read property 'buttons' of null(可通过查阅highcharts的API，其中有exporting 属性，即可知道原因。)
2.Uncaught Highcharts error #14: www.highcharts.com/errors/14
造成这个原因一般都是Highcharts的series里格式错误或者addPoint操作时格式错误，有时候你的数据来源是由后台加载，就必须注意通过aJax返回到前台的数据，必须是number(int float double等)的数据，而不是String.