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It seems that the only way of getting the value for the <code>null</code> key using standard EL implementation is to call <code>get()</code> method on the map (considering that you said <code>keyObject.keyProp</code> resolves to Integer object): <pre><code><c:out value="${map.get(keyObject.keyProp)}" /> </code></pre> I tested this solution and it works. Actually, in this case, you can easily do without <code><c:out /></code>, just use plain EL where you need it, e.g. <pre><code>${map.get(keyObject.keyProp)} </code></pre> <hr> <h2>Simple example:</h2> TestMapServlet.java <pre><code>package com.example; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.ServletException; import java.util.Map; import java.util.HashMap; import java.io.IOException; public class TestMapServlet extends HttpServlet { protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { Map<Integer, Object> map = new HashMap<Integer, Object>(); Integer noValueInt = null; Integer one = new Integer(1); Integer two = new Integer(2); map.put(noValueInt, "Default object for null Integer key"); map.put(one, "Object for key = Integer(1)"); map.put(two, "Object for key = Integer(2)"); request.setAttribute("map", map); request.setAttribute("noValueInt", noValueInt); request.setAttribute("one", one); request.setAttribute("two", two); request.getRequestDispatcher("/test-map.jsp").forward(request, response); } } </code></pre> test-map.jsp <pre><code><%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%> <!DOCTYPE html> <html> <head> <title>Home Page</title> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> </head> <body> <h1>Testing access to java.util.Map using just EL</h1> \${map.get(noValueInt)}: ${map.get(noValueInt)} \${map[one]}: ${map[one]} \${map[two]}: ${map[two]} <h1>Testing access to java.util.Map using JSTL and EL</h1> &lt;c:out value="\${map.get(noValueInt)}" /&gt; : <c:out value="${map.get(noValueInt)}" /> &lt;c:out value="\${map[one]}" /&gt; : <c:out value="${map[one]}" /> &lt;c:out value="\${map[two]}" /&gt; : <c:out value="${map[two]}" /> <h2>Printing java.util.Map keys and values (when Key = null, the null won't be shown)</h2> <c:forEach items="${map}" var="entry"> Key = "${entry.key}", Value = "${entry.value}" </c:forEach> </body> </html> </code></pre> web.xml <pre><code><?xml version="1.0" encoding="UTF-8"?> <web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0"> <servlet> <servlet-name>Test Map Servlet</servlet-name> <servlet-class>com.example.TestMapServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>Test Map Servlet</servlet-name> <url-pattern>/TestMap.do</url-pattern> </servlet-mapping> </web-app> </code></pre> IMPORTANT NOTE To be able to invoke methods with arguments using EL you must use minimum Servlet version 3.0. Quote from here: <a href="https://stackoverflow.com/tags/el/info">https://stackoverflow.com/tags/el/info</a> <blockquote> Since EL 2.2, which is maintained as part of Servlet 3.0 / JSP 2.2 (Tomcat 7, Glassfish 3, JBoss AS 6, etc), it's possible to invoke non-getter methods, if necessary with arguments. </blockquote> <hr> Apart from the above solution you could use custom Unified Expression Language implementation such as <a href="http://juel.sourceforge.net/index.html" rel="nofollow noreferrer">JUEL</a> that has an alternative solution. An explanation why it is not possible (in the standard implementation) to access map value by the <code>null</code> key using <code>[]</code> and the custom solution can be found in <a href="http://juel.sourceforge.net/juel.pdf" rel="nofollow noreferrer">Java Unified Expression Language (JUEL) documentation</a> (emphasis in paragraphs is mine): <blockquote> <h2>2.5. Advanced Topics</h2> ... <h3>Enabling/Disabling null Properties</h3> The EL specification describes the evaluation semantics of <code>base[property]</code>. If property is null, the specification states not to resolve null on base. Rather, null should be returned if <code>getValue(...)</code> has been called and a <code>PropertyNotFoundException</code> should be thrown else. As a consequence, it is impossible to resolve null as a key in a map. However, JUEL's expression factory may be configured to resolve null like any other property value. To enable (disable) null as an EL property value, you may set property <code>javax.el.nullProperties</code> to true (false). Assume that identifier map resolves to a <code>java.util.Map</code>. <ul> <li>If feature <code>javax.el.nullProperties</code> has been disabled, evaluating <code>${base[null]}</code> as an rvalue (lvalue) will return null (throw an exception). </li> <li>If feature <code>javax.el.nullProperties</code> has been enabled, evaluating <code>${base[null]}</code> as an rvalue (lvalue) will get (put) the value for key null in that map. The default is not to allow null as an EL property value. </li> </ul> ... </blockquote> Hope this will help.
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