Problem in many to one relation.

[chaitanya karthikk]

Hi all, I am facing a problem while trying to insert a record with foreign key.

There are two tables. "Surname" and "Family".

The hibernate files are

<?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="hibernate.pojo.Surname" table="surname">
        <id name="surname" type="string">
            <column name="sur_name" length="50" not-null="true" />
            <generator class="assigned" />
        </id>
    </class>
</hibernate-mapping>

<?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="hibernate.pojo.Family" table="family">
		<id name="id" type="long">
			<column name="id"></column>
			<generator class="hilo"></generator>
		</id>
		<property name="name" type="string">
			<column name="name" length="100" not-null="true"></column>
		</property>
		<many-to-one name="surname" class="hibernate.pojo.Surname" column="sur_name" not-null="true"></many-to-one>
	</class>
</hibernate-mapping>

Using this code I am trying to insert the record

package hibernate;

import hibernate.pojo.Family;
import hibernate.pojo.Surname;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;

public class ForeignKey
{
	public static void main(String kk[])
	{
		Configuration cfg=new Configuration();
		cfg=cfg.configure();
		SessionFactory factory=cfg.buildSessionFactory();
		Session session=factory.openSession();
		List<String> list=new ArrayList<String>();
		Query query=session.createQuery("select surname from Surname where surname like 'Thanuku'");
		Iterator it=query.iterate();
		for(;it.hasNext();)
		{
			list.add(it.next().toString());
		}
		session.close();
		session=factory.openSession();
		it=list.iterator();
		if(it.hasNext())
		{
			Family family=new Family();
			family.setName("Krishna");
			family.setSurname(it.next().toString());
			Transaction tx=session.beginTransaction();
			session.save(family);
			session.flush();
			tx.commit();
			session.close();
		}
	}
}

While executing the program I am getting errors like

Exception in thread "main" org.hibernate.PropertyAccessException: IllegalArgumentException
occurred calling getter of hibernate.pojo.Surname.surname
and
Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
ERROR - IllegalArgumentException in class: hibernate.pojo.Surname, getter method of property: surname

The table family is created successfully, but error is occurring while insertion.

Can anyone tell me how to fix it? Thank you all in advance.

[chaitanya karthikk]

Can anyone help me fix the problem.

[Stanley Walker]

Can you please post the code for the two entity classes which you are using. THere would be more clarity then.
thank you.

[chaitanya karthikk]

chaitanya karthikk wrote:Hi all, I am facing a problem while trying to insert a record with foreign key.

There are two tables. "Surname" and "Family".

The hibernate files are

<?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="hibernate.pojo.Surname" table="surname">
        <id name="surname" type="string">
            <column name="sur_name" length="50" not-null="true" />
            <generator class="assigned" />
        </id>
    </class>
</hibernate-mapping>

<?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="hibernate.pojo.Family" table="family">
		<id name="id" type="long">
			<column name="id"></column>
			<generator class="hilo"></generator>
		</id>
		<property name="name" type="string">
			<column name="name" length="100" not-null="true"></column>
		</property>
		<many-to-one name="surname" class="hibernate.pojo.Surname" column="sur_name" not-null="true"></many-to-one>
	</class>
</hibernate-mapping>

Using this code I am trying to insert the record

package hibernate;

import hibernate.pojo.Family;
import hibernate.pojo.Surname;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;

public class ForeignKey
{
	public static void main(String kk[])
	{
		Configuration cfg=new Configuration();
		cfg=cfg.configure();
		SessionFactory factory=cfg.buildSessionFactory();
		Session session=factory.openSession();
		List<String> list=new ArrayList<String>();
		Query query=session.createQuery("select surname from Surname where surname like 'Thanuku'");
		Iterator it=query.iterate();
		for(;it.hasNext();)
		{
			list.add(it.next().toString());
		}
		session.close();
		session=factory.openSession();
		it=list.iterator();
		if(it.hasNext())
		{
			Family family=new Family();
			family.setName("Krishna");
			family.setSurname(it.next().toString());
			Transaction tx=session.beginTransaction();
			session.save(family);
			session.flush();
			tx.commit();
			session.close();
		}
	}
}

Surname.java

package hibernate.pojo;

public class Surname
{
	private String surname;
	public void setSurname(String surname)
	{
		this.surname=surname;
	}
	public String getSurname()
	{
		return surname;
	}
}

Family.java

package hibernate.pojo;

public class Family
{
	private String surname;
	private long id;
	private String name;
	public void setSurname(String surname)
	{
		this.surname=surname;
	}
	public void setId(long id)
	{
		this.id=id;
	}
	public void setName(String name)
	{
		this.name=name;
	}
	public String getSurname()
	{
		return surname;
	}
	public long getId()
	{
		return id;
	}
	public String getName()
	{
		return name;
	}
}

While executing the program I am getting errors like

Exception in thread "main" org.hibernate.PropertyAccessException: IllegalArgumentException
occurred calling getter of hibernate.pojo.Surname.surname
and
Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
ERROR - IllegalArgumentException in class: hibernate.pojo.Surname, getter method of property: surname

The table family is created successfully, but error is occurring while insertion.

Can anyone tell me how to fix it? Thank you all in advance.

[chaitanya karthikk]

anyone there to help me

[chaitanya karthikk]

Anyone there who can help me, I provided with all the necessary files.

[chaitanya karthikk]

The issue has been solved, the POJO class is wrong and the family.hbm file is also wrong. I fixed it.