Tests with Projection API

marco-p · **Posted:** Tue Feb 08, 2005 1:55 pm

I'm trying to adapt a CriteriaPager I've used with the patched version of Hibernate2 to page criteria query results.
This components simply get a Criteria object, applies a RowCount projection to the query, executes it, gets the total row number for paging calculation, removes the projection, sets the MaxResults and FirstResult params and re-executes the query. When I execute the first query, I get an Exception:

Code:

org.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of web.model.Articolo.id
        at org.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:117)
        at org.hibernate.persister.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:673)
        at org.hibernate.persister.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:845)
        at org.hibernate.engine.ForeignKeys.isTransient(ForeignKeys.java:169)
        at org.hibernate.engine.ForeignKeys.getEntityIdentifierIfNotUnsaved(ForeignKeys.java:202)
        at org.hibernate.type.ManyToOneType.disassemble(ManyToOneType.java:98)
        at org.hibernate.cache.StandardQueryCache.put(StandardQueryCache.java:63)
        at org.hibernate.loader.Loader.list(Loader.java:1333)
        at org.hibernate.loader.CriteriaLoader.list(CriteriaLoader.java:106)
        at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1603)
        at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:257)
        at org.hibernate.impl.CriteriaImpl.uniqueResult(CriteriaImpl.java:373)
        at web.pager.CriteriaPager.init(CriteriaPager.java:72)
        at web.pager.CriteriaPager.getPageElements(CriteriaPager.java:130)
        at web.action.RicercaArticoloAction.go(RicercaArticoloAction.java:170)
        at web.action.AbstractAction.execute(AbstractAction.java:190)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:169)
[snip]

The code I execute:

Code:

criteria.setProjection( Projections.rowCount() );
            int elementsSize = 0;
            try {
                elementsSize = Integer.parseInt(criteria.uniqueResult().toString());
            } catch( Exception e ) {
                e.printStackTrace( System.out );
            }
            criteria.setProjection( null );

Any idea on this?
I'd like to receive comments on this component. I use it with WebWork, if I get this working I can contribute it, if anyone is interested.

Hibernate version:
Hibernate 3 beta 3

Mapping documents:
Articolo

Code:

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

<hibernate-mapping>

<class
    name="web.model.Articolo"
    table="ARTICOLO"
>
    <cache usage="read-write" />
    <id
        name="id"
        type="java.lang.String"
        column="ID"
    >
        <generator class="assigned" />
    </id>

    <property
        name="catalogo"
        type="java.lang.String"
        column="CATALOGO"
        length="64"
    />
[snip]
    <many-to-one
        name="genere"
        class="web.model.Genere"
        not-null="true"
    >
        <column name="GENEREID" />
    </many-to-one>
    <many-to-one
        name="autore"
        class="web.model.Autore"
        not-null="true"
    >
        <column name="AUTOREID" />
    </many-to-one>

</class>
</hibernate-mapping>

Autore

Code:

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

<hibernate-mapping>

<class
    name="web.model.Autore"
    table="AUTORE"
>
    <cache usage="read-write" />
    <id
        name="id"
        type="long"
        column="ID"
    >
        <generator class="assigned" />
    </id>

    <property
        name="nome"
        type="java.lang.String"
        column="NOME"
        length="256"
    />
    <property
        name="descrizione"
        type="java.lang.String"
        column="DESCRIZIONE"
        length="1024"
    />
    <property
        name="posizione"
        type="java.lang.String"
        column="POSIZIONE"
        length="256"
    />
    <set
        name="articoloList"
        lazy="true"
        inverse="true"
      cascade="none"
    >
        <key>
            <column name="AUTOREID" />
        </key>
        <one-to-many
            class="web.model.Articolo"
        />
    </set>

</class>
</hibernate-mapping>

Genere

Code:

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

<hibernate-mapping>
<class
    name="web.model.Genere"
    table="GENERE"
>
    <cache usage="read-write" />
    <id
        name="id"
        type="long"
        column="ID"
    >
        <generator class="assigned" />
    </id>

    <property
        name="nome"
        type="java.lang.String"
        column="NOME"
        length="64"
    />
    <set
        name="articoloList"
        lazy="true"
        inverse="true"
      cascade="none"
    >
        <key>
            <column name="GENEREID" />
        </key>
        <one-to-many
            class="web.model.Articolo"
        />
    </set>
    <many-to-one
        name="categoria"
        class="web.model.Categoria"
        not-null="true"
    >
        <column name="CATEGORIAID" />
    </many-to-one>

</class>
</hibernate-mapping>

Name and version of the database you are using:
Oracle DB 9.2.0.5

The generated SQL (show_sql=true):

Code:

Hibernate: select count(*) as y0_ from ARTICOLO this_ where lower(this_.ID) like ?

[/b]

marco-p · **Posted:** Wed Feb 09, 2005 6:04 am

I think I've figured out what's wrong.
I've enabled the cache on the criteria (setCacheable(true)), so Hibernate tries to get the Id of the returned record for cache handling, but it fails 'cause the id column is not available (projection!):

Stack trace:

Code:

org.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of cinetica.nannucci.web.model.Articolo.id
        at org.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:117)
        at org.hibernate.persister.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:673)
        at org.hibernate.persister.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:845)
        at org.hibernate.engine.ForeignKeys.isTransient(ForeignKeys.java:169)
        at org.hibernate.engine.ForeignKeys.getEntityIdentifierIfNotUnsaved(ForeignKeys.java:202)
        at org.hibernate.type.ManyToOneType.disassemble(ManyToOneType.java:98)
**************
        at org.hibernate.cache.StandardQueryCache.put(StandardQueryCache.java:63)
**************
        at org.hibernate.loader.Loader.list(Loader.java:1333)
        at org.hibernate.loader.CriteriaLoader.list(CriteriaLoader.java:106)
        at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1603)
        at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:257)
        at org.hibernate.impl.CriteriaImpl.uniqueResult(CriteriaImpl.java:373)
[snip]
Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:324)
        at org.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:103)
        ... 43 more

BTW, is there a way to obtain a copy of the criteria object, so I can set the projection and cache policy without altering the original criteria?

gavin · **Posted:** Wed Feb 09, 2005 6:32 am

oh, yes. criteria query caching dont support projection yet. woops.

gavin · **Posted:** Wed Feb 09, 2005 7:37 am

Fixed in CVS.

marco-p · **Posted:** Fri Feb 11, 2005 5:23 am

OK, it works ! Thanks