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[b]Hibernate version:3.0[/b]

[b]Mapping documents:
Parent.hbm.xml

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping
>
<class
name="com.gloptv.smsc.Parent"
table="parent"
lazy="false"
dynamic-update="false"
dynamic-insert="false"
select-before-update="false"
optimistic-lock="version"
>

<id
name="id"
column="id"
type="int"
>
<generator class="sequence">
<!--
To add non XDoclet generator parameters, create a file named
hibernate-generator-params-Parent.xml
containing the additional parameters and place it in your merge dir.
-->
</generator>
</id>

<property
name="name"
type="java.lang.String"
update="true"
insert="true"
access="property"
column="name"
not-null="true"
/>

<set
name="childrens"
lazy="true"
inverse="true"
cascade="all-delete-orphan"
sort="unsorted"
order-by="name"
>

<key
column="parent_id"
>
</key>

<one-to-many
class="com.gloptv.smsc.Children"
/>

</set>

<!--
To add non XDoclet property mappings, create a file named
hibernate-properties-Parent.xml
containing the additional properties and place it in your merge dir.
-->

</class>

</hibernate-mapping>

Children.hbm.xml
<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping
>
<class
name="com.gloptv.smsc.Children"
table="children"
lazy="false"
dynamic-update="false"
dynamic-insert="false"
select-before-update="false"
optimistic-lock="version"
>

<id
name="id"
column="id"
type="int"
>
<generator class="sequence">
<!--
To add non XDoclet generator parameters, create a file named
hibernate-generator-params-Children.xml
containing the additional parameters and place it in your merge dir.
-->
</generator>
</id>

<property
name="name"
type="java.lang.String"
update="true"
insert="true"
access="property"
column="name"
not-null="true"
/>

<many-to-one
name="parent"
class="com.gloptv.smsc.Parent"
cascade="save-update"
outer-join="auto"
update="true"
insert="true"
access="property"
column="parent_id"
not-null="true"
/>

<!--
To add non XDoclet property mappings, create a file named
hibernate-properties-Children.xml
containing the additional properties and place it in your merge dir.
-->

</class>

</hibernate-mapping>

[/b]

[b]Code between sessionFactory.openSession() and session.close():[/b]

[b]Full stack trace of any exception that occurs:[/b]

[b]Name and version of the database you are using:postgresql 8.0[/b]

[b]The generated SQL (show_sql=true):[/b]

[b]Debug level Hibernate log excerpt:[/b]

Hi, I have a class Parent and a class Children. One parent can have many children. My problem is as follows:

For example I delete a children for parent A and immediately output the size of the Set of childrens for parent A. Everything works fine.

Then I try the following:
Parent parent = Parent.getInstance(2);
Children child = Children.getInstance(8);

System.out.println("Nb children before: " +parent.getChildrens().size());
child.delete();
System.out.println("Nb children after: " + parent.getChildrens().size());

That is, I output the size of Set of Children before deleting, delete specfic children and finally output size of Set again. But I got the following exception when it executes the function child.delete():

Exception in thread "main" java.lang.Exception: deleted object would be re-saved by cascade (remove deleted object from associations): [com.
gloptv.smsc.Children#8]

Why is this happening? I've just do parent.getChildrens().size() before deleting and nothing seems to work.

thanks in advance

I assume that child.delete() is calling session.delete(this) or something like that ?

session.delete() does not modify the Java object. It only deletes the data from the database - assuming you commit the transaction.

If the parent collection has a reference to the child, the child object will still exist.

As a side note: If you cascade deletes from your parent to your child, you don't have to explicitly delete the child. Remove it from the parent collection and update the Parent.

Thanks for your reply, but even if I remove the child from the parent collection "childrens.remove(children)", I do get this exception.

My question is why do I get this exception if I do "parent.getChildrens().size()" before deleting a specific child.

Am sorry, when I do parent.deleteChildren() everything works fine. Even if I do a query before.

One more question, if I delete a parent by doing session.delete(this). Will everything will be fine with respect to db and java objects. As far as I know for database everything will be ok. I would like to know if its the same for the Java Object