Iterating through a List Object in JSP

Question

I am working on a project to try and teach myself spring and struts. I am currently stuck on a JSP page. I have a pojo class with variables eid and ename with getters/setters, I also have a table in sql with the same values with six populated rows.
I am accessing my database through a JdbcTemplate and have stored the result in a list, I then passed this list to my action page in which I set it as a request.setAttribute("empList",eList). In my jsp page I call that attribute and then try to iterate through it using JSTL.
However nothing shows up, I know that my list variable has data in it since i checked it using the expression tag <%=eList%> and objects show up like this:

[org.classes.database.Employee@d9b02, 
org.classes.database.Employee@13bce7e, 
org.classes.database.Employee@171cc79, 
org.classes.database.Employee@272a02, 
org.classes.database.Employee@137105d, 
org.classes.database.Employee@1359ad]

I thought that maybe I was missing something on jstl but I have jstl-1.2 in my META-INF/lib folder. I have also tried to add it in the configure path file and still nothing. I also have the correct tag url.
Also when I do a simple <c:out value="Hello"/>. Hello does print out. So this leads me to believe that my jstl is working properly, but when I try iterating through my list using jstl nothing shows up at all.

Anyways here is my JSP page:

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-   8859-1"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page import="java.util.List"%>
<!DOCTYPE html>
<% List eList = (List)session.getAttribute("empList");%>

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Employee Details</title>
</head>
<body>
<c:out value="Hello"></c:out>
<h3>Employee Details</h3>
<hr size="4" color="gray"/>
<table>
<%=eList%>
    <c:forEach items="${eList}" var="employee">
        <tr>
            <td>Employee ID: <c:out value="${employee.eid}"/></td>
            <td>Employee Pass: <c:out value="${employee.ename}"/></td>  
        </tr>
    </c:forEach>
</table>
</body>
</html>

Any help would be highly appreciated!

Sotirios Delimanolis · Accepted Answer · 2021-08-28T22:48:57.487

Before teaching yourself Spring and Struts, you should probably dive a little deeper into the Java language. Output like this

org.classes.database.Employee@d9b02

is the result of the Object#toString() method which all objects inherit from the Object class, the superclass of all classes in Java.

The List sub classes implement this by iterating over all the elements and calling toString() on those. It seems, however, that you haven't implemented (overriden) the method in your Employee class.

Your JSTL here

<c:forEach items="${eList}" var="employee">
    <tr>
        <td>Employee ID: <c:out value="${employee.eid}"/></td>
        <td>Employee Pass: <c:out value="${employee.ename}"/></td>  
    </tr>
</c:forEach>

is fine except for the fact that you don't have a page, request, session, or application scoped attribute named eList.

You need to add it

<% List eList = (List)session.getAttribute("empList");
   request.setAttribute("eList", eList);
%>

Or use the attribute empList in the forEach.

<c:forEach items="${empList}" var="employee">
    <tr>
        <td>Employee ID: <c:out value="${employee.eid}"/></td>
        <td>Employee Pass: <c:out value="${employee.ename}"/></td>  
    </tr>
</c:forEach>

score 5 · Answer 2 · answered Dec 26 '13 at 18:22

5

change the code to the following

<%! List eList = (ArrayList)session.getAttribute("empList");%>
....
<table>
    <%
    for(int i=0; i<eList.length;i++){%>
        <tr>
            <td><%= ((Employee)eList[i]).getEid() %></td>
            <td><%= ((Employee)eList[i]).getEname() %></td>  
        </tr>
      <%}%>
</table>

answered Dec 26 '13 at 18:22

Alaa Abuzaghleh

1,023
6
11

7

Please don't suggest scriptlets as an alternative to EL and jstl. – Sotirios Delimanolis Dec 26 '13 at 18:24
2

@Alaa Abuzaghleh Read about Why Not to Use Scriptlets http://www.coderanch.com/how-to/java/WhyNotUseScriptlets – Prabhaker A Dec 26 '13 at 18:32

score 4 · Answer 3 · answered Dec 26 '13 at 18:17

4

you can read empList directly in forEach tag.Try this

 <table>
       <c:forEach items="${sessionScope.empList}" var="employee">
            <tr>
                <td>Employee ID: <c:out value="${employee.eid}"/></td>
                <td>Employee Pass: <c:out value="${employee.ename}"/></td>  
            </tr>
        </c:forEach>
    </table>

answered Dec 26 '13 at 18:17

Prabhaker A

8,317
1
18
24

@jjcode you're welcome.`sessionScope` implicit object gives the session scope attribute, so no need to go for script let.Read more about EL implicit objects http://www.journaldev.com/2064/jsp-expression-language-el-example-tutorial – Prabhaker A Dec 26 '13 at 18:36

score 0 · Answer 4 · answered Jun 23 '17 at 10:02

0

 <c:forEach items="${sessionScope.empL}" var="emp">
            <tr>
                <td>Employee ID: <c:out value="${emp.eid}"/></td>
                <td>Employee Pass: <c:out value="${emp.ename}"/></td>  
            </tr>
        </c:forEach>

answered Jun 23 '17 at 10:02

Savan Makone

11
2

score -2 · Answer 5 · answered Jan 24 '17 at 00:58

another example with just scriplets, when iterating through an ArrayList that contains Maps.

<%   
java.util.List<java.util.Map<String,String>> employees=(java.util.List<java.util.Map<String, String>>)request.getAttribute("employees");    

for (java.util.Map employee: employees) {
%>
<tr>
<td><input value="<%=employee.get("fullName") %>"/></td>    
</tr>
...
<%}%>

Iterating through a List Object in JSP

5 Answers5

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