[OPENJPA-329] Generic interface may cause the openjpa Reflection code to pickup the wrong getter method

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.0.2, 1.1.0
• Component/s: jpa
• Assignee: Unassigned
• Reporter: Henry Lai
• Created: 22/Aug/07 22:10
• Updated: 09/Mar/10 18:32
• Resolved: 31/Jan/08 00:01

Description

The test case

public void testFind()

{ PersistenceProviderImpl openJPA = new PersistenceProviderImpl(); EntityManagerFactory factory = openJPA.createEntityManagerFactory("test", "ptp/test/issue6/persistence.xml", System.getProperties() ); EntityManager em = factory.createEntityManager(); em.getTransaction().begin(); String query="select obj from T6Entity obj where obj.name=?1"; Query queryObject = em.createQuery(query); queryObject.setParameter(1, "Mom"); List resultList = queryObject.getResultList(); em.getTransaction().commit(); em.close(); }

produces the following exception

<1.0.0-SNAPSHOT-SNAPSHOT fatal user error> org.apache.openjpa.persistence.ArgumentException: Collection field "ptp.test.issue6.T6Entity.children" declares that it is mapped by "ptp.test.issue6.T6Entity.parent", but this is not a valid inverse relation.
at org.apache.openjpa.jdbc.meta.MappingRepository.useInverseKeyMapping(MappingRepository.java:903)
at org.apache.openjpa.jdbc.meta.MappingRepository.defaultTypeStrategy(MappingRepository.java:838)
at org.apache.openjpa.jdbc.meta.MappingRepository.defaultStrategy(MappingRepository.java:771)
at org.apache.openjpa.jdbc.meta.RuntimeStrategyInstaller.installStrategy(RuntimeStrategyInstaller.java:62)

public interface ITree <T extends ITree> {
public List<T> getChildren();
public T getParent();
}

public class T6Entity implements ITree {

private Long id;
T6Entity parent;
List<T6Entity> children;

public T6Entity getParent()

{ return parent; }

public Long getId()

{ return id; }

public void setId(Long id)

{ this.id = id; }

public List<T6Entity> getChildren()

{ return children; }

public void setChildren(List<T6Entity> children)

{ this.children = children; }

public void setParent(T6Entity parent)

{ this.parent = parent; }

public void addChild(T6Entity aChild) {
if ( children == null )

{ children = new ArrayList<T6Entity>(); }

children.add( aChild );
aChild.setParent(this);
}

}

<entity class="T6Entity">
<table name="T6Entity" />
<attributes>
<id name="id">
<column name="S_ID" />
<generated-value strategy="SEQUENCE" generator="seqGen1" />
<sequence-generator name="seqGen1" sequence-name="SEQ_OBJECT_ID" />
</id>

<many-to-one name="parent" fetch="EAGER">
<join-column name="PARENT_ID" />
<cascade>
<cascade-persist />
<cascade-merge />
</cascade>
</many-to-one>
<one-to-many name="children"
target-entity="T6Entity"
mapped-by="parent" fetch="LAZY">
<cascade>
<cascade-persist />
<cascade-merge />
</cascade>
</one-to-many>
</attributes>
</entity>

The java compiler generate the following 2 method for getParent()

public volatile ptp.test.issue6.ITree ptp.test.issue6.T6Entity.getParent()
public ptp.test.issue6.T6Entity ptp.test.issue6.T6Entity.getParent()

and depending on the order of the methods return from the reflection getDeclaredMethod(), it cause the wrong return type to be infer as the inverse relationship.

There is a work around, by specifying the target-entity in the many-to-one mapping.

But may be something that should be fix.

Issue Links

• relates to: OPENJPA-251 org.apache.openjpa.enhance.Reflection.getDeclaredMethod() has undefined behavior, leading to VM-dependent crashes