Foreign key not being set when saving Object child arrays

tnine · **Joined:** Fri Feb 13, 2004 10:02 pm **Posts:** 90

This is my hibernate file that contains all of the mappings for my classes.

Code:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
   "-//Hibernate/Hibernate Mapping DTD//EN"
   "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>

    <!-- org.teamcharlie.modal.Trigger root -->
    <class name="org.teamcharlie.modal.Trigger" table="Trigger">
        <id name="id" type="int" column="id" unsaved-value="0">
            <generator class="native"/>
        </id>
        <property name="name" column="name" type="string"/>
        <property name="state" column="state" type="string"/>
    </class>

    <!-- org.teamcharlie.modal.Instance root -->
    <class name="org.teamcharlie.modal.Instance" table="Instance">
        <id name="id" type="int" column="id" unsaved-value="0">
            <generator class="native"/>
        </id>
        <property name="name" column="name" type="string"/>
    </class>

    <!-- org.teamcharlie.modal.CIMMethod root -->
    <class name="org.teamcharlie.modal.CIMMethod" table="Method">
        <id name="id" type="int" column="id" unsaved-value="0">
            <generator class="native"/>
        </id>
        <many-to-one name="overRiddenMethod" column="overRiddenMethod" class="org.teamcharlie.modal.CIMMethod"/>
        <property name="methodName" column="methodName" type="string"/>
        <property name="returnType" column="returnType" type="string"/>
        <array name="triggers" table="Triggers" cascade="all">
            <key column="uid_triggers"/>
            <index column="idx_triggers"/>
            <one-to-many class="org.teamcharlie.modal.Trigger"/>
        </array>
        <array name="parameters" table="Parameters" cascade="all">
            <key column="uid_parameters"/>
            <index column="idx_parameters"/>
            <element column="elm" type="string"/>
        </array>
    </class>
    <!-- org.teamcharlie.modal.NamedElement root -->
    <class name="org.teamcharlie.modal.NamedElement" table="NamedElement">
        <id name="id" type="int" column="id" unsaved-value="0">
            <generator class="native"/>
        </id>
        <property name="name" column="name" type="string"/>
        <array name="qualifiers" table="Qualifier" cascade="all">
            <key column="uid_qualifiers"/>
            <index column="idx_qualifiers"/>
            <one-to-many class="org.teamcharlie.modal.Qualifier"/>
        </array>
    </class>

    <!-- org.teamcharlie.modal.Property root -->
    <class name="org.teamcharlie.modal.Property" table="Property">
        <id name="id" type="int" column="id" unsaved-value="0">
            <generator class="native"/>
        </id>
        <property name="name" column="name" type="string"/>
        <many-to-one name="overridenProperty" column="overridenProperty" class="org.teamcharlie.modal.Property"/>
        <array name="triggers" table="Trigger" cascade="all">
            <key column="uid_triggers"/>
            <index column="idx_triggers"/>
            <one-to-many class="org.teamcharlie.modal.Trigger"/>
        </array>
        <property name="type" column="type" type="string"/>
        <array name="qualifiers" table="qualifiers" cascade="all">
            <key column="uid_qualifiers"/>
            <index column="idx_qualifiers"/>
            <one-to-many class="org.teamcharlie.modal.Qualifier"/>
        </array>
        <property name="value" column="value" type="string"/>
    </class>

    <!-- org.teamcharlie.modal.Qualifier root -->
    <class name="org.teamcharlie.modal.Qualifier" table="Qualifier">
        <id name="id" type="int" column="id" unsaved-value="0">
            <generator class="native"/>
        </id>
        <property name="defaultValue" column="defaultValue" type="string"/>
        <property name="flavor" column="flavor" type="string"/>
        <property name="name" column="name" type="string"/>
        <property name="scope" column="scope" type="string"/>
        <many-to-one name="type" class="org.teamcharlie.modal.QualifierType"/>
        <property name="value" column="value" type="string"/>
    </class>

    <!-- org.teamcharlie.modal.QualifierType root -->
    <class name="org.teamcharlie.modal.QualifierType" table="QualifierType">
        <id name="id" type="int" column="id" unsaved-value="0">
            <generator class="native"/>
        </id>
        <property name="type" column="type" type="string"/>
    </class>

    <!-- org.teamcharlie.modal.Reference root -->
    <class name="org.teamcharlie.modal.Reference" table="Reference">
        <id name="id" type="int" column="id" unsaved-value="0">
            <generator class="native"/>
        </id>
        <property name="name" column="name" type="string"/>
        <many-to-one name="overridenProperty" column="overridenProperty" class="org.teamcharlie.modal.Property"/>
        <array name="triggers" table="Trigger" cascade="all">
            <key column="uid_triggers"/>
            <index column="idx_triggers"/>
            <one-to-many class="org.teamcharlie.modal.Trigger"/>
        </array>
        <property name="type" column="type" type="string"/>
        <array name="qualifiers" table="qualifiers" cascade="all">
            <key column="uid_qualifiers"/>
            <index column="idx_qualifiers"/>
            <one-to-many class="org.teamcharlie.modal.Qualifier"/>
        </array>
        <property name="value" column="value" type="string"/>
        <many-to-one name="referencedClass" column="referencedClass" class="org.teamcharlie.modal.CIMClass"/>
    </class>

    <!-- org.teamcharlie.modal.CIMClass root -->
    <class name="org.teamcharlie.modal.CIMClass" table="Class">
        <id name="id" type="int" column="id" unsaved-value="0">
            <generator class="native"/>
        </id>
        <property name="version" column="version" type="string"/>
        <array name="methods" table="Methods" cascade="all" inverse="true">
            <key column="uid_methods"/>
            <index column="idx_methods"/>
            <one-to-many class="org.teamcharlie.modal.CIMMethod"/>
        </array>
        <property name="name" column="name" type="string"/>
        <array name="properties" table="Property" cascade="all" inverse="true">
            <key column="uid_properties"/>
            <index column="idx_properties"/>
            <one-to-many class="org.teamcharlie.modal.Property"/>
        </array>
        <array name="triggers" table="Triggers" cascade="all" inverse="true">
            <key column="uid_triggers"/>
            <index column="idx_triggers"/>
            <one-to-many class="org.teamcharlie.modal.Trigger"/>
        </array>
        <many-to-one name="parentClass" column="parentClass" class="org.teamcharlie.modal.CIMClass"/>
        <array name="instances" table="Instances" cascade="all" inverse="true">
            <key column="uid_instances"/>
            <index column="idx_instances"/>
            <one-to-many class="org.teamcharlie.modal.Instance"/>
        </array>
        <joined-subclass name="org.teamcharlie.modal.Association" table="Association">
            <key column="class_id"/>
            <array name="references" table="Reference" cascade="all" inverse="true">
                <key column="uid_references"/>
                <index column="idx_references"/>
                <one-to-many class="org.teamcharlie.modal.Reference"/>
            </array>
        </joined-subclass>
        <joined-subclass name="org.teamcharlie.modal.Indication" table="Indication">
            <key column="class_id"/>
        </joined-subclass>
    </class>
    <!-- org.teamcharlie.modal.Schema root -->
    <class name="org.teamcharlie.modal.Schema" table="Schema">
        <id name="id" type="int" column="id" unsaved-value="0">
            <generator class="native"/>
        </id>
        <property name="version" column="version" type="string"/>
        <property name="name" column="name" type="string"/>
        <array name="classes" table="classes" cascade="all">
            <key column="uid"/>
            <index column="idx"/>
            <one-to-many class="org.teamcharlie.modal.CIMClass"/>
        </array>
    </class>


</hibernate-mapping>

In a JUnit test, using cactus I run the following setup to add 3 temporary objects to my database.

Code:

       super.setUp();

        //this sesion of code cleans up the database
        Session session = HibernateSession.getInstance().getSession();

        //Add A, B, and C to the database

        CIMClass A = new CIMClass();
        A.setName("A");
        A.setVersion("1");
        A.setProperties(
                new Property[]{
                    new Property(0, "A prop1", "String", "", null, null, null),
                    new Property(0, "A prop2", "String", "", null, null, null)
                }
        );

        A.setMethods(
                new CIMMethod[]{
                    new CIMMethod(0, "A method1", "void", new String[]{"param1", "param2"}, null, null),
                    new CIMMethod(0, "A method2", "void", new String[]{"param1", "param2"}, null, null)
                }
        );

        A.setInstances(new Instance[]{new Instance(0, "A instance")});

        CIMClass B = new CIMClass();

        B.setName("B");
        B.setVersion("1");

        //set the parent class to A
        B.setParentClass(A);

        B.setProperties(
                new Property[]{
                    new Property(0, "B prop1", "String", "", null, null, null),
                    new Property(0, "B prop2", "String", "", null, null, null)
                }
        );

        B.setMethods(
                new CIMMethod[]{
                    new CIMMethod(0, "B method1", "void", new String[]{"param1", "param2"}, null, null),
                    new CIMMethod(0, "B method2", "void", new String[]{"param1", "param2"}, null, null)
                }
        );

        B.setInstances(new Instance[]{new Instance(0, "A instance")});

        CIMClass C = new CIMClass();


        C.setName("C");
        C.setVersion("1");
        //Set parent Class
        C.setParentClass(A);

        C.setProperties(
                new Property[]{
                    new Property(0, "C prop1", "String", "", null, null, null),
                    new Property(0, "C prop2", "String", "", null, null, null)
                }
        );

        C.setMethods(
                new CIMMethod[]{
                    new CIMMethod(0, "C method1", "void", new String[]{"param1", "param2"}, null, null),
                    new CIMMethod(0, "C method2", "void", new String[]{"param1", "param2"}, null, null)
                }
        );

        C.setInstances(
                new Instance[]{
                    new Instance(0, "C instance 1"),
                    new Instance(0, "C instance 1")
                });

        //save them in the databse
        session.save(A);
        session.save(B);
        session.save(C);
        session.flush();
        session.close();

Hoever, when I look in the database, the key column is null for all of the child object arrays of the CIMClass. For instance, the Class table has the row.

Code:

'id','version','name','parentClass','uid','idx'
'16','1','A','[NULL]','[NULL]','[NULL]'

And these are two rows in the method table

Code:

'id','overRiddenMethod','methodName','returnType','uid_methods','idx_methods'
'31','[NULL]','A method1','void','[NULL]','[NULL]'
'32','[NULL]','A method2','void','[NULL]','[NULL]'

As you can see, the uid_methods property never gets set to the value of class.id. However when I delete the objects, all child objects in the array are deleted as well. Does anyone have any clue as to why this is happening or how to fix it?

Thanks,
Todd.

Myk · **Joined:** Sun Jan 04, 2004 2:46 pm **Posts:** 147

Probably because you have a single-directional relationship between Class and Method and in the one-to-many section in Class for the Methods inverse is set to true. This means setting the relationship in this direction ( adding to the methods array ) has no effect on the db. Try removing the inverse='true' in the CIMClass methods property. You should see the relationships getting updated then.

Check the generated SQL before and after to see what it is doing wrong now and what it does with the change.

Cheers.

Myk.

tnine · **Joined:** Fri Feb 13, 2004 10:02 pm **Posts:** 90

Myk,
Thanks for the help, I removed the inverse="true", and now after flush is called the foreign keys are there. You're a lifesafer! We start implementation of our business logic on Monday, and this needed corrected by then.

Thanks again!
Todd

l.masini · **Posted:** Mon Feb 16, 2004 4:32 am

Making it inverse="true" is REALLY a good idea, cause can improve performance of your application.
The fact is that when you mantain relationship with inverse="true", you must mantain the relationship on the otherside. I mean that when you add Method to Class, you must also set Class into Method, that's what create the fk.
Also, remember that cascade="all" with inverse="true" is not possible.
You can read all I said on the documentation.
Ciao.

Myk · **Joined:** Sun Jan 04, 2004 2:46 pm **Posts:** 147

inverse='true' is used for bidirectional relationships. This relationship only goes from Class to Method, there is no link from Method to class so inverse='true' shouldn't be used and it is not possible to set the Method's Class, this happens implicitly by adding to the Method array in Class.

Cheers.

Myk.