之前试过<mvc:resources>和<mvc:default-servlet-handler>,都不管用。经过尝试采用了下面的方法，加载成功。
首先是目录结构：
common-js.jsp是我为了避免重复引用静态资源而写的通用的jsp页面。在common-js.jsp中引入静态资源，其他的jsp页面只需要适用<jsp:include>引入common-js.jsp即可适用静态资源而不需要在每个jsp页面都重复编写加载静态资源的代码。
下面是common-js.jsp的代码：
<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8"%><%String contextPath=request.getContextPath();//替代 ${pageContext.request.contextPath }写法；//js和css是不能放在WEB-INFX下的。否则会访问不到%><link rel="stylesheet" type="text/css" href="<%=contextPath %>/js/jquery-easyui-1.4.1/themes/default/easyui.css" /><link rel="stylesheet" type="text/css" href="<%=contextPath %>/js/jquery-easyui-1.4.1/themes/icon.css" /><link rel="stylesheet" type="text/css" href="<%=contextPath %>/css/taotao.css" /><script type="text/javascript" src="<%=contextPath %>/js/jquery-easyui-1.4.1/jquery.min.js"></script><script type="text/javascript" src="<%=contextPath %>/js/jquery-easyui-1.4.1/jquery.easyui.min.js"></script><script type="text/javascript" src="<%=contextPath %>/js/jquery-easyui-1.4.1/locale/easyui-lang-zh_CN.js"></script><script type="text/javascript" src="<%=contextPath %>/js/common.js"></script>
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><%String contextPath = request.getContextPath();%><title>淘淘商城后台管理系统</title><style type="text/css">.content {padding: 10px 10px 10px 10px;}</style></head><jsp:include page="common-js.jsp"></jsp:include><body class="easyui-layout"><div data-options="region:'west',title:'菜单',split:true" style="width:180px;"><ul id="menu" class="easyui-tree" style="margin-top: 10px;margin-left: 5px;"><li><span>商品管理</span><ul><li data-options="attributes:{'url':'/rest/page/item-add'}">新增商品</li><li data-options="attributes:{'url':'/rest/page/item-list'}">查询商品</li><li data-options="attributes:{'url':'/rest/page/item-param-list'}">规格参数</li></ul></li><li><span>网站内容管理</span><ul><li data-options="attributes:{'url':'/rest/page/content-category'}">内容分类管理</li><li data-options="attributes:{'url':'/rest/page/content'}">内容管理</li></ul></li></ul></div><div data-options="region:'center',title:''"><div id="tabs" class="easyui-tabs"><div title="首页" style="padding:20px;"></div></div></div><script type="text/javascript">$(function(){$('#menu').tree({onClick: function(node){if($('#menu').tree("isLeaf",node.target)){var tabs = $("#tabs");var tab = tabs.tabs("getTab",node.text);if(tab){tabs.tabs("select",node.text);}else{tabs.tabs('add',{title:node.text,href: node.attributes.url,closable:true,bodyCls:"content"});}}}});});</script></body></html>
上面是需要引入common-js.jsp的index.jsp页面的代码。在<head>和<body>标签之间加上这句话： 注意,common-js.jsp是和引入它的jsp放在WEB-INF下的，也必须放在WEB-INF下，否则会加载不到！
<jsp:include page="common-js.jsp"></jsp:include>
放在web-app下加载不到common-js.jsp的错误如下：
javax.servlet.ServletException: File "/WEB-INF/jsps/common-js.jsp" not foundat org.apache.jasper.servlet.JspServlet.handleMissingResource(JspServlet.java:412)at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:379)at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:749)at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:605)at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:544)at org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:954)at org.apache.jsp.WEB_002dINF.jsps.index_jsp._jspService(index_jsp.java:80)at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)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:728)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:749)at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:487)at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:412)at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:339)at org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:209)at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:266)at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1225)at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1012)at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:876)at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:931)at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:822)at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:807)at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:108)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)at org.apache..JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)at java.lang.Thread.run(Thread.java:722)
因此common-js.jsp必须也放在WEB-INF下。
下面是样式加载成功的效果：
