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Exception in column using addJoin in Native SQL Hibernate

I'm using Hibernate 5.2.8, I have the tables Departamentos and Empleados. Departamentos.java
private int deptNo;
private String dnombre;
private String loc;
private Set<Empleados> empleadoses = new HashSet<Empleados>(0);
Empleados.java
private int empNo;
private Departamentos departamentos;
......
Departamentos HBM
<hibernate-mapping auto-import="true" default-access="property" default-cascade="none" default-lazy="true">
<class catalog="hibernate" dynamic-insert="false" dynamic-update="false" mutable="true" name="jdbc.Departamentos" optimistic-lock="version" polymorphism="implicit" select-before-update="false" table="departamentos">
<id name="deptNo" type="int">
<column name="dept_no"/>
<generator class="assigned"/>
</id>
.........
<set embed-xml="true" fetch="select" inverse="true" lazy="true" mutable="true" name="empleadoses" optimistic-lock="true" sort="unsorted" table="empleados">
<key on-delete="noaction">
<column name="dept_no" not-null="true"/>
</key>
<one-to-many class="jdbc.Empleados" embed-xml="true" not-found="exception"/>
</set>
</class>
Empleados HBM
<hibernate-mapping auto-import="true" default-access="property" default-cascade="none" default-lazy="true">
<class catalog="hibernate" dynamic-insert="false" dynamic-update="false" mutable="true" name="jdbc.Empleados" optimistic-lock="version" polymorphism="implicit" select-before-update="false" table="empleados">
<id name="empNo" type="int">
<column name="emp_no"/>
<generator class="assigned"/>
</id>
<many-to-one class="jdbc.Departamentos" embed-xml="true" fetch="select" insert="true" name="departamentos" not-found="exception" optimistic-lock="true" unique="false" update="true">
<column name="dept_no" not-null="true"/>
</many-to-one>
......
This is the query:
Query q = session.createSQLQuery("SELECT e.emp_no,e.apellido,e.oficio, d.dnombre FROM empleados e inner join departamentos d on e.dept_no=d.dept_no "
+ "where d.dnombre LIKE '"+dep+"'")
.addEntity("e",jdbc.Empleados.class)
//.addEntity("d",jdbc.Departamentos.class)
.addJoin("d","e.departamentos");
Exception:
ERROR: Column 'dept_no' not found. Exception in thread "main" org.hibernate.exception.SQLGrammarException: could not execute query
How to resolve this problem?

Hibernate Error indexing: null when checking if row exists

I am trying to check if a row exists in my database.
Word word = (Word) session.createQuery("select 1 from Word w where w.content = :key").setParameter("key",words[i]).uniqueResult();
I'm also trying:
Word word = session.get(Word.class,contentId);
Besides that I tried session.load,and some others. Everytime Hibernate returns error:
Error indexing: null
or
Error indexing: no row with the given identifier exists.
It is true, row does not existing but why doesn't it just returns null like it should for session.get:
http://docs.jboss.org/hibernate/orm/3.5/javadocs/org/hibernate/Session.html#get(java.lang.Class,%20java.io.Serializable).
In case of not finding a row I wanted to create one and add to a database but I'm not able to check if it exists.
EDIT:
Word.java
public class Word {
private String content;
private Set<Sentence> sentences;
empty constructor, setters and getters
}
Word.hbm.xml
<class name="Word">
<id name="content" column="wordId" type="string">
</id>
<set name="sentences" inverse="true">
<key><column name="wordId"/></key>
<many-to-many class="Sentence" column="sentenceId"/>
</set>
</class>
Sentence.java
public class Sentence {
private long id;
private ProcessedUrl processedUrl;
private List<Word> words;
empty constructor, setters and getters
}
Sentence.hbm.xml
<class name="Sentence">
<id name="id" column="sentenceId">
<generator class="native"/>
</id>
<many-to-one name="processedUrl" column="processedUrlId" not-null="true"/>
<list name="words">
<key>
<column name="sentenceId" not-null="true"/>
</key>
<list-index column="idx" />
<many-to-many class="Word">
<column name="wordId" not-null="true"/>
</many-to-many>
</list>
</class>

Hibernate org.hibernate.LazyInitializationException: could not initialize

I have two classes :
Etudiant and Pays
In the database the table Etudiant has a foreign key for the table Pays.
In my code I have something like this :
List<Etudiant> listEtudiants = (List<Etudiant>) etudiantService.getAll();
for(Etudiant etudiant : listEtudiants) {
if(((JTextField)arg0.getSource()).getText().equals(etudiant.getNom())){
System.out.println(etudiant.getPays().getNom());
}
}
but when I run this code it fails with the exception:
org.hibernate.LazyInitializationException: could not initialize proxy - no Session
In the line :
System.out.println(etudiant.getPays().getNom());
Mapping for Etudiant:
<hibernate-mapping>
<class name="tp.ihm.domain.Etudiant" table="etudiant" schema="public" optimistic-lock="version">
<id name="numInsc" type="java.lang.Long">
<column name="num_insc" />
<generator class="assigned" />
</id>
<many-to-one name="pays" class="tp.ihm.domain.Pays" fetch="select">
<column name="pays" not-null="true" />
</many-to-one>
<property name="nom" type="string">
<column name="nom" length="50" not-null="true" />
</property>
<property name="prenom" type="string">
<column name="prenom" length="50" not-null="true" />
</property>
</class>
</hibernate-mapping>
Mapping for Pays:
<hibernate-mapping>
<class name="tp.ihm.domain.Pays" table="pays" schema="public" optimistic-lock="version">
<id name="id" type="java.lang.Long">
<column name="id" />
<generator class="assigned" />
</id>
<property name="nom" type="string">
<column name="nom" length="45" not-null="true" />
</property>
<set name="etudiants" table="etudiant" inverse="true" lazy="true" fetch="select">
<key>
<column name="pays" not-null="true" />
</key>
<one-to-many class="tp.ihm.domain.Etudiant" />
</set>
</class>
</hibernate-mapping>
I tried to remove the fetch attribute in the mapping for Pays, and then to change it's value to eager but nothing works.
Could someone please help me with this ?
Edit :
This is the code for the getAll method :
public List getAll() throws EntityNotFoundException {
// Get the current session
Session s = getSession();
List list = null;
// If the BLL layer started a transaction
// In this case it is the BLL layer that manages the session and transaction
if (anActiveTransactionExist(s)) {
list = s.createCriteria(Etudiant).list();
} else {
LOGGER.debug("DAO initialize its own transaction");
Transaction tx = null;
try {
// Starts a transaction locally
tx = s.beginTransaction();
list = s.createCriteria(boClass).list();
tx.commit();
} catch (RuntimeException ex) {
// Cancel the transaction if there is a problem
handleDaoOpError(tx, ex);
} finally {
closeSession(s);
}
}
if (list == null || list.size() == 0)
throw new EntityNotFoundException();
return list;
}

You need to change the mapping of Etudiant from fetch=select to fetch=join
fetch-“join” = Disable the lazy loading, always load all the collections and entities.
fetch-“select” (default) = Lazy load all the collections and entities.
<many-to-one name="pays" class="tp.ihm.domain.Pays" fetch="join">
<column name="pays" not-null="true" />
</many-to-one>

Hibernate 1 to M restriction on children

I have 1 to M association with Country and Person. Meaning a Country can have multiple persons. The country.hbm.xml fils is shown below:
<?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 package="com.test.hibernate">
<class name="Country">
<id name="countryId" column="CountryID" > </id>
<property name="countryName" column="CountryName" length="50"></property>
<set name="persons" table="Person" fetch="select" inverse="true">
<key>
<column name="CountryId" not-null="true"></column>
</key>
<one-to-many class="com.test.hibernate.Person"/>
</set>
</class>
</hibernate-mapping>
The Person.hbm.xml is shown below
<?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 package="com.test.hibernate">
<class name="Person">
<id name="personID" column="PersonID" > </id>
<property name="name" column="Name" length="50"></property>
<property name="age" column="Age"></property>
<property name="gender" column="Gender" length="1"></property>
<property name="email" column="Email" length="50"></property>
<property name="countryID" column="CountryID" insert="false" update="false"></property>
<many-to-one name="Country" class="com.test.hibernate.Country" fetch="select">
<column name="CountryID" not-null="true"></column>
</many-to-one>
</class>
</hibernate-mapping>
Now, I am trying to query all the persons who are males belonging to India Country
Criteria countryCriteria = session.createCriteria(Country.class);
Criterion country = Restrictions.eq("countryName", "India");
Criterion male = Restrictions.eq("persons.gender", "M");
countryCriteria.add(country);
countryCriteria.add(male);
List<Country> countryList = countryCriteria.list();
I am getting a
Exception in thread "main" org.hibernate.QueryException: could not resolve property: persons.gender of: com.test.hibernate.Country
at org.hibernate.persister.entity.AbstractPropertyMapping.propertyException(AbstractPropertyMapping.java:83)
at org.hibernate.persister.entity.AbstractPropertyMapping.toColumns(AbstractPropertyMapping.java:98)
at org.hibernate.persister.entity.BasicEntityPropertyMapping.toColumns(BasicEntityPropertyMapping.java:61)
at org.hibernate.persister.entity.AbstractEntityPersister.toColumns(AbstractEntityPersister.java:1960)
at org.hibernate.loader.criteria.CriteriaQueryTranslator.getColumns(CriteriaQueryTranslator.java:523)
at org.hibernate.loader.criteria.CriteriaQueryTranslator.findColumns(CriteriaQueryTranslator.java:538)
at org.hibernate.criterion.SimpleExpression.toSqlString(SimpleExpression.java:66)
at org.hibernate.loader.criteria.CriteriaQueryTranslator.getWhereCondition(CriteriaQueryTranslator.java:419)
at org.hibernate.loader.criteria.CriteriaJoinWalker.(CriteriaJoinWalker.java:123)
at org.hibernate.loader.criteria.CriteriaJoinWalker.(CriteriaJoinWalker.java:92)
at org.hibernate.loader.criteria.CriteriaLoader.(CriteriaLoader.java:95)
at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1643)
at org.hibernate.internal.CriteriaImpl.list(CriteriaImpl.java:374)
at com.test.hibernate.Main.main(Main.java:54)
Please help. I am new to Hibernate.
Thanks in advance.

Country.personsis of type Collection<Person>. A Collection doesn't have any property named "gender".
If you used HQL instead of Criteria (and you should, for such a simple static query), you would have to do a join:
select c from Country c
join country.persons person
where c.countryName = 'India'
and person.gender = 'M'
You thus have to do the same with the Criteria query:
Criteria countryCriteria = session.createCriteria(Country.class, "c");
countryCriteria.createALias("c.persons", "person");
countryCriteria.add(Restrictions.eq("c.countryName", "India"));
countryCriteria.add(Restrictions.eq("person.gender", "M"));
List<Country> countryList = countryCriteria.list();

I used M to 1 and used Criteria on Person object as opposed to Country Object.
Criteria personCriteria = session.createCriteria(Person.class,"p");
personCriteria.createAlias("p.Country", "c");
Criterion gender = Restrictions.eq("gender", "M");
Criterion country = Restrictions.eq("c.countryName", "India");
personCriteria.add(gender);
personCriteria.add(country);
List<Person> personList = personCriteria.list();
This way the personList had all the Persons who were males and belonged to India.

Mapping same class relation

Hi
I’m trying to map some classes in hibernate there and have general problem how such mapping can be done.
There is User class and Facebook user class which has the following structure
User Class :
public class User{
public User(){}
Long Id;
String FirstName;
String LastName;
....
FbUser fbuser;
//// all requred
getters and setters...
}
Facebook class FbUser can have list of Friends which are objects of the same class FbUser.
public class FbUser{
public FbUser(){}
Long fbId;
String FirstName;
String LastName;
List<FbUser> friends;
//// all requred
getters and setters...
}
Till now I made many to one relation between User And FbUser.
<hibernate-mapping>
<class
name="User"
table="User"
>
<id
name="Id"
column="ID"
type="java.lang.Long"
unsaved-value="null"
>
<generator class="increment"/>
</id>
<property
name="FirstName"
update="true"
insert="true"
not-null="false"
unique="false"
type="java.lang.String"
>
<column name="FirstName" />
</property>
<property
name="LastName"
update="true"
insert="true"
not-null="false"
unique="false"
type="java.lang.String"
>
<column name="LastName" />
</property>
<many-to-one
name="fbUser"
class="FbUser"
cascade="all"
column="fbId"
unique="true"
/>
</class>
</hibernate-mapping>
And now the FbUser Mapping:
<hibernate-mapping>
<class
name="FbUser"
table="FbUser"
>
<id
name="fbId"
column="fbId"
type="java.lang.Long"
unsaved-value="null"
>
<generator class="increment"/>
</id>
<property
name="FirstName"
update="true"
insert="true"
not-null="false"
unique="false"
type="java.lang.String"
>
<column name="FirstName" />
</property>
<property
name="LastName"
type="java.lang.String"
update="true"
insert="true"
column="LastName"
not-null="true"
unique="false"
/>
</class>
</hibernate-mapping>
Chow can I map FbUser List inside the FbUser Map file? I got lost :(

You can create an additional class named, for instance, MyFriends
public class FbUser {
List<MyFriends> friends = new ArrayList<MyFriends>();
}
Just relevant part
If you have a index-column
<hibernate-mapping>
<class name="FbUser">
<list name="myFriends">
<key column="ME_ID" insert="false" update="false"/>
<list-index column="WHICH COLUMN SHOULD BE USED AS INDEX"/>
<one-to-many class="MyFriends"/>
</list>
</class>
</hibernate-mapping>
If you do not have a index-column
re-write your list as
public class FbUser {
Collection<MyFriends> friends = new ArrayList<MyFriends>();
}
And
<hibernate-mapping>
<class name="FbUser">
<bag name="columns">
<key column="ME_ID" insert="false" update="false"/>
<one-to-many class="MyFriends"/>
</bag>
</class>
</hibernate-mapping>
And your MyFriends mapping. Notice you need a composite primary key (implemented as a static inner class)
<class name="MyFriends">
<composite-id name="myFriendsId" class="MyFriends$MyFriendsId">
<key-property name="meId"/>
<key-property name="myFriendId"/>
</composite-id>
<many-to-one name="me" class="FbUser" insert="false" update="false"/>
<many-to-one name="myFriend" class="FbUser" insert="false" update="false"/>
</class>
Your MyFriends is shown as follows
public class MyFriends {
private MyFriendsId myFrinedId;
private FbUser me;
private FbUser myFriend;
public static class MyFriendsId implements Serializable {
private Integer meId;
private Integer myFriendId;
// getter's and setter's
public MyFriendsId() {}
public MyFriendsId(Integer meId, Integer myFriendId) {
this.meId = meId;
this.myFriendId = myFriendId;
}
// getter's and setter's
public boolean equals(Object o) {
if(!(o instanceof MyFriendsId))
return false;
MyFriendsId other = (MyFriendsId) o;
return new EqualsBuilder()
.append(getMeId(), other.getMeId())
.append(getMyFriendId(), other.getMyFriendId())
.isEquals();
}
public int hashcode() {
return new HashCodeBuilder()
.append(getMeId())
.append(getMyFriendId())
.hashCode();
}
}
}

Well, first: User has a one-to-one relation with FbUser, correct?
second: Map FbUser to FbUser as a many to many relation using a list or a set. I have an Set example here:
<set
name="friends"
table="FbUser" <!-You may use other table here if you want->
access="field">
<key
column="fbId"/>
<many-to-many
class="bla.bla.bla.FbUser"
column="friend_id" />
</set>