HashMap<String, HashMap<Integer, String>> hMap = new HashMap<String, HashMap<Integer,String>>();

HashMap<Integer, String> xx = new HashMap<Integer, String>();
xx.put (1, "ABC");
xx.put (2, "def");

HashMap<Integer, String> yy = new HashMap<Integer, String>();
yy.put (1, "ABC");
yy.put (2, "def");

hMap.put ("20120826", xx);
hMap.put ("20120827", yy);

request.setAttribute("hoursByProjectByDay", hMap);

ArrayList<String> displyDtArr = new ArrayList<String>();
displyDtArr.add("20120826");
displyDtArr.add("20120827");
request.setAttribute("displayDates", displyDtArr);

ArrayList<Integer> projects= new ArrayList<Integer>();
projects.add(1)
projects.add(2);
request.setAttribute("projects", projects);


      <c:forEach var="pl" items="${projects}">
 <c:forEach var="displayDt" items="${displayDates}">
    <c:forEach var="hoursByProjByday" items="${hoursByProjectByDay[displayDt]}">
            <c:set var="userHour"  value="${hoursByProjByday[pl]}"/>

        </c:forEach>
    </c:forEach>
</c:forEach>

org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:524)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:435)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
edu.uchospitals.timetrack.FrontController.dispatch(FrontController.java:121)
edu.uchospitals.timetrack.FrontController.processRequest(FrontController.java:116)
edu.uchospitals.timetrack.FrontController.doPost(FrontController.java:152)
javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)

root cause
javax.el.PropertyNotFoundException: Property '1' not found on type java.util.HashMap$Entry
javax.el.BeanELResolver$BeanProperties.get(BeanELResolver.java:193)
javax.el.BeanELResolver$BeanProperties.access$400(BeanELResolver.java:170)
javax.el.BeanELResolver.property(BeanELResolver.java:279)
javax.el.BeanELResolver.getValue(BeanELResolver.java:60)
javax.el.CompositeELResolver.getValue(CompositeELResolver.java:53)
org.apache.el.parser.AstValue.getValue(AstValue.java:97)
org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:923)
org.apache.jsp.WEB_002dINF.jsp.main_jsp._jspx_meth_c_005fset_005f0(main_jsp.java:548)
org.apache.jsp.WEB_002dINF.jsp.main_jsp._jspx_meth_c_005fforEach_005f5(main_jsp.java:513)
org.apache.jsp.WEB_002dINF.jsp.main_jsp._jspx_meth_c_005fforEach_005f4(main_jsp.java:471)
org.apache.jsp.WEB_002dINF.jsp.main_jsp._jspx_meth_c_005fforEach_005f1(main_jsp.java:338)
org.apache.jsp.WEB_002dINF.jsp.main_jsp._jspService(main_jsp.java:138)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:393)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
edu.uchospitals.timetrack.FrontController.dispatch(FrontController.java:121)
edu.uchospitals.timetrack.FrontController.processRequest(FrontController.java:116)
edu.uchospitals.timetrack.FrontController.doPost(FrontController.java:152)
javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)

<c:forEach var="project" items="${projects}">
    <c:forEach var="displayDt" items="${displayDates}">
        <c:forEach var="userHours" items="${hoursByProjectByDay[displayDt][project]}">
             <br/>${userHours}
        </c:forEach>
    </c:forEach>
</c:forEach>