Iterate multilevel collection in jsp

Question

I found difficulties in iterating a multilevel collection on jsp.

@Entity
@Table(name = "Establishment")
public class Establishment extends Basis<Long> {

@Column(name = "code")
private Long code;    // will be used for link to the entity if the name will be updated
@Column(nullable = false)
private String name;
private String establishmentType;

@ManyToOne(optional = true)
private Establishment establishment;
@Column(name = "establishment_id", insertable = false, updatable = false)
private Long establishmentId;

@OneToMany(mappedBy = "establishment", orphanRemoval = true, cascade = CascadeType.ALL)
private List<Establishment> establishments = new ArrayList<>();

//getters & setters
}

jsp code

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ page session="true" %>
<%@ taglib tagdir="/WEB-INF/tags" prefix="myTags" %>

<myTags:hierarchy list="${establishmentList}"/>

tag file:

<%@ attribute name="list" required="true" %>
<%@ taglib tagdir="/WEB-INF/tags" prefix="myTags" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>
<c:if test="${!empty list}">
<ul>
    <c:forEach var="entity" items="${list}">
        <li><c:out value="${entity.name}"/></li>
        <%--${fn:length(e.establishments)}--%>
        <myTags:hierarchy list="${entity.establishments}"/>
    </c:forEach>
</ul>
</c:if>

if i use 'list' in <c:forEach var="entity" items="${list}"> like here I cannot use ${entity.name}, if use <c:forEach var="entity" items="${establishmentList}"> i get recursive call of first-only element. So, how should I edit tag file to make this work?

score 0 · Answer 1 · answered Apr 24 '15 at 13:39

The solution isn't so far :)

The line <%@ attribute name="list" required="true" %> is responsible for the configuration of the types we want to iterate. If we want to operate with ArrayList (this case) we should use <%@ attribute name="list" type="java.util.ArrayList<by.ipps.accounting.model.Establishment>" required="false" %>.

I've found the idea of "type" parameter here but the things are seem not to be the same.

Iterate multilevel collection in jsp

1 Answers1