Hi.

i'm new to Hibernate Annotations please help me.?

I want create the one-to-many relationship with two tables only .

For eg I have configured through hbm.xml its fine what i expected :

<?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="Admin" table="user" lazy="false">
<id name="userid" type="long" column="user_id">
<generator class="increment"/>
</id>
<bag name="roles" lazy="false" cascade="all">
<key column="user_id"/>
<one-to-many class="Role"/>
</bag>

<property name="username" type="string" column="user_name"/>
<property name="password" type="string" column="password"/>
<property name="firstname" type="string" column="first_name"/>
<property name="lastname" type="string" column="last_name"/>
</class>

<class name="Role" table="role" >
<id name="roleid" type="long" column="role_id">
<generator class="increment"/>
</id>
<property name="usergroupname" type="string" column="user_group_name"/>
<property name="status" type="string" column="status"/>
</class>
</hibernate-mapping>

I need same result with Annotations ,what i mentioned above configuration.

I hope I can get Quick Reply.

Thanks,
Malli.

Then with Annotations you must declare it as bidirectional OneToMany relation with inverse-owner (=use mappedBy attribute),
otherwise a 3thd table (a join-table) is needed.

Hi,

Thanks for your quick reply ..but still i'm getting exception.

i'm pasting the my java files and My TestCae file please help me out .where i did mistakes>

1.) Admin.java
=======================
package com.config.entities.oneToMany.twoTables.questinAndChoicwe;
import java.util.HashSet;
import java.util.Set;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;

@Entity
@Table (name="user")
public class Admin {

@Id
@GeneratedValue(strategy=GenerationType.TABLE)
@Column(name="user_id")
private long id;

@Column(name="admin_name")
private String name ;

@OneToMany(mappedBy="user_id", fetch = FetchType.EAGER)
private Set<Role> role = new HashSet<Role>();

public long getId() {
return id;
}

public void setId(long id) {
this.id = id;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public Set<Role> getRole() {
return role;
}

public void setRole(Set<Role> role) {
this.role = role;
}

}

2.) Role.java

package com.config.entities.oneToMany.twoTables.questinAndChoicwe;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Table;

@Entity
@Table(name="role")
public class Role {

@Id
@GeneratedValue(strategy=GenerationType.TABLE)
@Column(name="role_id")
private long id;

@Column(name="role_name")
private String rolename ;

@ManyToOne
private Admin user_id;


public long getId() {
return id;
}

public void setId(long id) {
this.id = id;
}

public String getRolename() {
return rolename;
}

public void setRolename(String rolename) {
this.rolename = rolename;
}

public Admin getUser_id() {
return user_id;
}

public void setUser_id(Admin userId) {
user_id = userId;
}

}

3.) AdminTest.java

package com.config.entities.oneToMany.twoTables.questinAndChoicwe;

import java.util.HashSet;
import java.util.Set;
import junit.framework.TestCase;
import com.config.daoimp.AnnoTaionDAOSupport;
import com.config.hibernatetemplate.XCalDataSource;

public class AdminTest extends TestCase {

public void testQuestion(){
AnnoTaionDAOSupport<Admin> lDAO=(AnnoTaionDAOSupport)XCalDataSource.clsAppContext.getBean("myUserDAO");
Admin lAdmin = new Admin();
lAdmin.setName("abc");
Role lRole = new Role();
lRole.setRolename("manager");
Set<Role> lRoleSet = new HashSet<Role>();
lAdmin.setRole(lRoleSet);
lDAO.saveUser(lAdmin);
}
}


TABLE STRUCTURE :
==================

CREATE TABLE user(user_id INT NOT NULL AUTO_INCREMENT ,admin_name VARCHAR(10) , PRIMARY KEY(user_id));

CREATE TABLE role(role_id INT NOT NULL AUTO_INCREMENT,
user_id INT NOT NULL ,role_name VARCHAR(10),
PRIMARY KEY(role_id),
CONSTRAINT `0-11` FOREIGN KEY(user_id) REFERENCES user (user_id));






EXCEPTION :
===================



java.lang.ExceptionInInitializerError
at com.config.entities.oneToMany.twoTables.questinAndChoicwe.AdminTest.testQuestion(AdminTest.java:14)
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:597)
at junit.framework.TestCase.runTest(TestCase.java:154)
at junit.framework.TestCase.runBare(TestCase.java:127)
at junit.framework.TestResult$1.protect(TestResult.java:106)
at junit.framework.TestResult.runProtected(TestResult.java:124)
at junit.framework.TestResult.run(TestResult.java:109)
at junit.framework.TestCase.run(TestCase.java:118)
at junit.framework.TestSuite.runTest(TestSuite.java:208)
at junit.framework.TestSuite.run(TestSuite.java:203)
at org.junit.internal.runners.OldTestClassRunner.run(OldTestClassRunner.java:35)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:46)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mySessionFactory' defined in class path resource [com/config/spring/persistence_annotations.xml]: Invocation of init method failed; nested exception is org.hibernate.AnnotationException: Collection has neither generic type or OneToMany.targetEntity() defined: com.config.entities.oneToMany.twoTables.questinAndChoicwe.Question.choice
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1338)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:473)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run(AbstractAutowireCapableBeanFactory.java:409)
at java.security.AccessController.doPrivileged(Native Method)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:264)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:423)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:728)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:380)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
at com.config.hibernatetemplate.XCalDataSource.<clinit>(XCalDataSource.java:16)
... 20 more
Caused by: org.hibernate.AnnotationException: Collection has neither generic type or OneToMany.targetEntity() defined: com.config.entities.oneToMany.twoTables.questinAndChoicwe.Question.choice
at org.hibernate.cfg.annotations.CollectionBinder.getCollectionType(CollectionBinder.java:521)
at org.hibernate.cfg.annotations.CollectionBinder.bind(CollectionBinder.java:417)
at org.hibernate.cfg.AnnotationBinder.processElementAnnotations(AnnotationBinder.java:1614)
at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:754)
at org.hibernate.cfg.AnnotationConfiguration.processArtifactsOfType(AnnotationConfiguration.java:546)
at org.hibernate.cfg.AnnotationConfiguration.secondPassCompile(AnnotationConfiguration.java:291)
at org.hibernate.cfg.Configuration.buildMappings(Configuration.java:1162)
at org.springframework.orm.hibernate3.LocalSessionFactoryBean.buildSessionFactory(LocalSessionFactoryBean.java:673)
at org.springframework.orm.hibernate3.AbstractSessionFactoryBean.afterPropertiesSet(AbstractSessionFactoryBean.java:211)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1369)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1335)
... 35 more

This message say that hibernate is missing the information about the target entity in the OneToMany relation,
you must either declare the collection using generics (=specify the target type between <>):



or by specifying the target Entity as annotation attribute:

Hi,

Sorry still i'm facing same problem..




as per above my modified java file like this

@OneToMany(mappedBy="user_id",targetEntity=Role.class)
private Set<Role> role = new HashSet<Role>();


can you please rectify me ,where i have did the mistakes..?

And my TestCase is fine ..Or i have written wrong ?

can you provide me if you have any samples ?

Thanks,
Malli.

May there be another OntToMany relation which causes the problem?

Please enable following loggings in your log4j.properties file and report the output, thanks