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POPassing variable from servlet to JSP
 

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    <p>I've seen other questions similar to this asked but none of them have helped me solve my problem. Basically, I'm trying to pass a variable from a servlet to a JSP.</p> <p>The servlet code.</p> <pre><code>package com.servlets; import java.io.IOException; import java.util.ArrayList; import javax.servlet.annotation.WebServlet; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.dao.DataGetter; @WebServlet("/DataGetterServlet") public class DataGetterServlet extends HttpServlet { private static final long serialVersionUID = 1L; ArrayList&lt;String[]&gt; data; private DataGetter dg; public void init() throws ServletException { try { dg = new DataGetter(); data = dg.getData(); } catch (Exception e) { throw new ServletException("An exception occurred in DataGetterServlet: " + e.getClass().getName()); } } protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setAttribute("data", data); RequestDispatcher rd = request.getRequestDispatcher("index.jsp"); rd.forward(request, response); } } </code></pre> <p>My JSP code</p> <pre><code>&lt;%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%&gt; &lt;%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %&gt; &lt;!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"&gt; &lt;html&gt; &lt;head&gt; &lt;meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"&gt; &lt;title&gt;Data extractor&lt;/title&gt; &lt;/head&gt; &lt;body&gt; Data table: &lt;table boder="1"&gt; &lt;c:forEach var="item" items="${data}" &gt; &lt;tr&gt; &lt;c:forEach var="column" items="${item}"&gt; &lt;td&gt;${column}&lt;/td&gt; &lt;/c:forEach&gt; &lt;/tr&gt; &lt;/c:forEach&gt; &lt;/table&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>I have done some tests with the forEach tag and JSTL is setup properly. I think the variable "data" is not reaching the JSP. Any idea why?</p> <p>Thanks in advance.</p> <p><strong>EDIT:</strong> For clarification porpuses. I have tried </p> <pre><code>&lt;c:forEach var="i" begin="1" end="5"&gt; Item &lt;c:out value="${i}"/&gt;&lt;p&gt; &lt;/c:forEach&gt; </code></pre> <p>And that works, but</p> <pre><code>&lt;c:forEach var="item" items="${data}"&gt; It worked!&lt;p&gt; &lt;/c:forEach&gt; </code></pre> <p>doesn't work. This is what has led me to believe that that variable data is not reaching the JSP for some reason.</p> <p><strong>EDIT 2:</strong> To run it, I configured a Tomcat server on Eclipse. I right click on the servlet and choose Run As -> Run on Server. The server restarts and I launch <code>http://localhost:8080/DataExtractor/</code> from my browser. Here's the resulting html:</p> <pre><code>&lt;!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"&gt; &lt;html&gt; &lt;head&gt; &lt;meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"&gt; &lt;title&gt;Data extractor&lt;/title&gt; &lt;/head&gt; &lt;body&gt; Data table: &lt;table border="1"&gt; &lt;/table&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p><strong>EDIT 3:</strong> This might be the key of why this is happening. When I go to <code>http://localhost:8080/DataExtractor/</code> (index.jsp), I get the html posted in <strong>Edit 2</strong>, but if I go to <code>http://localhost:8080/DataExtractor/DataGetterServlet</code> then I do get the right page! Any idea why?</p>
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    1. COAre you sure that the "data" array variable in the servlet actually has values when you are adding it to the request?
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      1. USSimon Arsenault
    2. COYes, I've checked and I can say for sure that the ArrayList is properly populated.
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    3. COAre you sure your arrayList is not empty list? If it is empty, then the loop won't iterate
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      1. USPrasad Kharkar
 

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