我写了一个javascript函数在javaweb标签a的onclick事件中调用为什么不执行

<%@ page language="java" import="java.util.*" pageEncoding="gbk"%>
<html>
<head>
<script src="javascript/leftmenu.js" type="text/javascript"></script>
<link href="CSS2/leftmenu.css" type="text/css" rel="stylesheet"/>
<style type="text/css">
.STYLE1 {
color: #CC6600
}
</style>
<script language="javaScript" type="text/javascript">
</script>
</head>
<body onload="open()">
<div id="leftmenu">
<div id="folder" onClick="open()" ondblclick=" open()">
<img id="folderclose" src="images/midclosedfolder.gif"/>
<img id="clsf" src="images/clsfld.gif" onmouseup="open()"/>
<a href="#" onClick="open()">产品管理</a>
</div>
<div id="productType" style="display:none">
<img id="folderclose" src="images/lastnodeline.gif">
<span class="STYLE1"><img id="clsf" src="images/doctemp.gif">产品类型管理</span>
</div>
<div id="productFolder" style="display:none">
<img id="folderclose" src="images/lastnodeline.gif">
<img id="clsf" src="images/doctemp.gif">
<span class="STYLE1" onclick="open()">文件管理</span>
</div>
<div id="worker" style="display:none">
<img id="folderclose" src="images/lastnodeline.gif">
<img id="clsf" src="images/doctemp.gif">
<span class="STYLE1">员工管理</span>
</div>
</div>
</body></html>