Hi, Is there any particular reason that 1 entity can not have 2 references of another table, ie, the entity has FK aID1 and aID2 that refers to different records of another table? I checked the hibernate 3.2 implementation in
org.hibernate.mapping.PersistentClass.checkPropertyDuplication

Seems to me that it is only using local data structure to make sure no 2 referenced tables are of the same name.

thank you for any hints



[b]Hibernate version: 3.2 [/b]

[b]Mapping documents:
<?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="popclonerecords.Mytest" table="mytest">
<id name="id" column="id" type="integer" unsaved-value="0">
<generator class="increment"/>
</id>



<many-to-one
name="testBranch"
column="t1ID"
class="popclonerecords.TestBranch"
not-null="true" />


<many-to-one
name="testBranch"
column="t2ID"
class="popclonerecords.TestBranch2"
not-null="true" />


</class>

</hibernate-mapping>
[/b]

[b]Code between sessionFactory.openSession() and session.close():
TestBranch tb = new TestBranch();
TestBranch2 tb2 = new TestBranch2();

Mytest cmap = new Mytest();
cmap.setTestBranch(tb);
cmap.setTestBranch2(tb2);
[/b]

[b]Full stack trace of any exception that occurs:
The exception is org.hibernate.MappingException:
org.hibernate.MappingException: Duplicate property mapping of testBranch found in mypack.Mytest


org.hibernate.mapping.PersistentClass.checkPropertyDuplication(PersistentClass.java:459)
org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:449)
org.hibernate.mapping.RootClass.validate(RootClass.java:192)
org.hibernate.cfg.Configuration.validate(Configuration.java:1102)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1287)
popclonerecords.TestParentChild.main(TestParentChild.java:156)

[/b]

[b]Name and version of the database you are using:[/b]
MySQL 4.0.27

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

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


Problems with Session and transaction handling?

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PS: TestBranch2 and TestBranch map to the same table

Is there a typo in your mapping? From your mapping, you are mapping two different entities (that map to the same table), to the same property name of your class.

Maybe this is what you want:

<class name="popclonerecords.Mytest" table="mytest">
<id name="id" column="id" type="integer" unsaved-value="0">
<generator class="increment"/>
</id>

<many-to-one
name="testBranch"
column="t1ID"
class="popclonerecords.TestBranch"
not-null="true" />

<many-to-one
name="testBranch2"
column="t2ID"
class="popclonerecords.TestBranch2"
not-null="true" />

</class>

thank you for your reply. Unfortunately, 2 entities (TestBranch & TestBranch2) do map to the same table. I created 2 entities only to comply with JavaBean's naming scheme. They are precisely identical except for the class name. Or Hibernate would complain that it can't find the getter of the property that is not named as its class name with the first letter underscored.

I understand that there are 2 entities mapped to the same table. The typo I'm referring to is the attribute name. Your mapping shows both entities mapped to the same attribute name. I don't think that is intended. Here is how I envision your source files and mapping:


Mytest.java
---------------
package popclonerecords;

public class Mytest implements Serializable {

private Integer id;
private TestBranch testBranch;
private TestBranch2 testBranch2;

public Mytest() {}

public Integer getId() { return id; }
public void setId(Integer id) { this.id = id; }

public TestBranch getTestBranch() { return testBranch; }
public void setTestBranch(TestBranch tb) { this.testBranch = tb; }

public TestBranch2 getTestBranch2() { return testBranch2; }
public void setTestBranch2(TestBranch2 tb) { this.testBranch2 = tb; }
}

hibernate.cfg.xml (or other mapping file)
-----------------------
<class name="popclonerecords.Mytest" table="mytest">
<id name="id" column="id" type="integer" unsaved-value="0">
<generator class="increment"/>
</id>

<many-to-one
name="testBranch"
column="t1ID"
class="popclonerecords.TestBranch"
not-null="true" />

<many-to-one
name="testBranch2"
column="t2ID"
class="popclonerecords.TestBranch2"
not-null="true" />

</class>

<class name="popclonerecords.TestBranch" table="TEST_BRANCH">
<id name="id" column="id" type="integer" unsaved-value="0">
<generator class="assigned" />
</id>
...
</class>

<class name="popclonerecords.TestBranch2" table="TEST_BRANCH">
<id name="id" column="id" type="integer" unsaved-value="0">
<generator class="assigned" />
</id>
...
</class>

Thank you so much for your reply and spending time to write down such a clear elucidation! It is my mal-understanding rather than a typo. Now everything works just as I like. Very grateful for your help