@ElementCollection using xml configuration

Question

I'm trying to persist an Object which have a set of Strings to database, I found that I must use @ElementCollection to do that, but since I'm using .hbm.xml configuration files through all my project I want to do it using xml . this question Hibernate, List<String> shows how to do it through annotations, and this link http://en.wikibooks.org/wiki/Java_Persistence/ElementCollection provides tips to do it using xml. But when I tried to use <element-collection> my eclipse IDE didn't accept it and gave me an error at the element <class/> which says the contents of element class must match ...

my class is simply like this

public class Role {
private Long id;
private Integer version;
private String name;
private Set<String> menuItems;
/** getters and setters **/

and my Role.hbm.xml is like this:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.element.collection.beans">
    <class name="Role" table="Role">
    <id name="id" type="java.lang.Long" column="id">
        <generator class="org.hibernate.id.TableHiLoGenerator">
            <param name="table">HibernateUniqueKey</param>
            <param name="column">NexHiValue</param>
        </generator>
    </id>
<version name="version" column="Version" />
<property name="name" column="name" type="java.lang.String"
        not-null="true" length="128" />

 <element-collection name="menuItems">
<collection-table>menuItems</collection-table>
</element-collection>

</class>

update:

here is the last mapping of the set, the rest is not changed

    <set name="menuItems" sort="unsorted" table="menuItems" lazy="false">
        <key column="itemId" />
        <element column="itemName" type="string" />
    </set>

Community · Accepted Answer · 2017-05-23 12:03:50Z

3

Check the doc:

And the example from that source:

<set name="aliases"
            table="person_aliases" 
            sort="natural">
    <key column="person"/>
    <element column="name" type="string"/>
</set>

So the answer is <element>

Example 7.16. <element> tag for collection values using mapping files

This <element> could be used in any type of colleciton mapping, like <bag> <set> <list>...

Also could be interesting: Understading the restrictions for collection of dependent objects in hibernate ...

Based on more details, we could say, that the mapping here would be like:

<class name="Role" table="Role">
    ...

    <set name="menuItems" sort="unsorted" table="menuItems" lazy="false">
        <key column="menuId" /> // not itemId
        <element column="itemName" type="string" />
    </set>
</class>

edited May 23, 2017 at 12:03

CommunityBot

11 silver badge

answered Sep 8, 2014 at 9:12

Radim Köhler

124k48 gold badges243 silver badges343 bronze badges

Sign up to request clarification or add additional context in comments.

8 Comments

Monim Over a year ago

I get an Exception when trying to save a role cannot insert null into menuItems.menuId

Radim Köhler Over a year ago

Could you show me the latest mapping? We will find it I guess ;) Just show me what you have (extend the answer I'd say)

Radim Köhler Over a year ago

I would say I got it! Look Exception says: cannot insert null into menuItems.menuId but the mapping is <key column="itemId" /> and it must be <key column="menuId" />

Monim Over a year ago

sorry but I just wrote it wrong, the Exception says: org.hibernate.exception.ConstraintViolationException: ORA-01400: cannot insert NULL into ("HUB"."MENUITEMS"."ITEMID") and I'm using <column = "itemId"/>

Radim Köhler Over a year ago

That is really weird. Look, in case Hibernate is mapped properly, this simple scenario is working always. So, check my answer and doc, compare it with what you really do have (DB vs mapping). This is very easy scenario... (having many of these mappings)

|

Collectives™ on Stack Overflow

@ElementCollection using xml configuration

update:

1 Answer 1

8 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

update:

1 Answer 1

8 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related