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JPA ManyToMany anotation for not load all items in set

I have User class and BattleReportILogItem class. This class (User, BattleReportILogItem) are #Entity.
User have 0..N BattleReportILogItem.
USER
#Entity
#Table(name = DomainConstant.TABLE_USER)
public class User implements Serializable {
#Id
#Column(name = DomainConstant.DOMAIN_USER_ID)
#GeneratedValue
private Long userId;
#ManyToMany(cascade = {CascadeType.ALL})
#JoinTable(name = DomainConstant.VIEW_USER_BATTLE_LOGS, joinColumns = {
#JoinColumn(name = DomainConstant.DOMAIN_USER_ID)}, inverseJoinColumns = {
#JoinColumn(name = DomainConstant.DOMAIN_BATTLE_REPORT_ID)})
private Set<BattleReportILogItem> setOfBattleLogs = new HashSet<>();
....(other stuff, get and set methods...)
BattleReportILogItem
#Entity
#Table(name = DomainConstant.TABLE_BATTLE_REPORT)
public class BattleReportILogItem implements Serializable {
#Id
#GeneratedValue
#Column(name = DomainConstant.DOMAIN_BATTLE_REPORT_ID)
private Long BattleReportILogItemId;
#ManyToMany(mappedBy = "setOfBattleLogs")
private Set<User> setOfBattleLogs = new HashSet<>();
....(other stuff, get and set methods...)
The problem is, that I load User program loads all data in private Set<BattleReportILogItem> setOfBattleLogs = new HashSet<>();. This mean 1 000 000 000 items in my set setOfBattleLogs. I don't want load data to this set. For load data i have BattleReportLogItemDao DAO.
Is there any solution how to NOT LOAD DATA to my set?
I hope, you understand me... :-))
Thank you for your help.
EDIT persistence.xml:
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="2.0">
<persistence-unit name="com.donutek" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
<properties>
<property name="hibernate.hbm2ddl.auto" value="update"/>
<property name="openjpa.jdbc.SynchronizeMappings" value="buildSchema"/>
<property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>
<property name="hibernate.connection.password" value=""/>
<property name="hibernate.connection.username" value="root"/>
<property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/db"/>
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5InnoDBDialect"/>
<property name="hibernate.validator.apply_to_ddl" value="true" />
<property name="connection.provider_class" value="org.hibernate.connection.C3P0ConnectionProvider"/>
<property name="hibernate.c3p0.min_size" value="5"/>
<property name="hibernate.c3p0.max_size" value="20"/>
<property name="hibernate.c3p0.timeout" value="300"/>
<property name="hibernate.c3p0.max_statements" value="50"/>
<property name="hibernate.c3p0.idle_test_period" value="300"/>
</properties>
</persistence-unit>
</persistence>
EDIT 2:
For load user I am using the code:
#Override
public User findByEmail(String email) {
TypedQuery<User> q = em.createQuery("SELECT u FROM " + User.class.getSimpleName() + " u WHERE u.email = :uemail", User.class);
q.setParameter("uemail", email);
try {
return q.getSingleResult();
} catch (NoResultException e) {
return null;
}
}

You can use the parameter fetchtype Lazy. Now your strategy seems to be Eager.

Hibernate Auto Detection in Persistence.xml Not Working

I've read Do I need <class> elements in persistence.xml? and How to auto detect entities in JPA 2.0 and followed their tag useage in my persistence.xml, but Entitys are not being auto detected by Hibernate. When I remove the <class> tag this no longer works and I get a MappingException. For some reason I can't seem to enable auto detection. NOTE this is a stand-alone hibernate application (shouldn't matter as far as I know). I have this example:
Persistence.xml:
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
<persistence-unit name="Test_Project" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>com.gmail.physicistsarah.gradletestproject.core.Person</class>
<!--Exclude unlisted class detection-->
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<properties>
<!-- Scan for annotated classes and Hibernate mapping XML files -->
<property name="hibernate.archive.autodetection" value="class, hbm"/>
<property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/test_project_db?zeroDateTimeBehavior=convertToNull"/>
<property name="javax.persistence.jdbc.user" value="root"/>
<property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
<property name="javax.persistence.jdbc.password" value=""/>
<property name="hibernate.cache.provider_class" value="org.hibernate.cache.NoCacheProvider"/>
<property name="javax.persistence.schema-generation.database.action" value="none"/>
<!--<property name="hibernate.show_sql" value="true"/>-->
<property name="hibernate.hbm2ddl.auto" value="create"/>
</properties>
</persistence-unit>
Person:
package com.gmail.physicistsarah.gradletestproject.core;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;
/**
*
* #author Sarah Szabo
*/
#Entity
#Table(name = "Person")
public class Person {
#Id
#GeneratedValue
#Column(name = "Person_ID")
private final int id = 0;
#Column(name = "First_Name", nullable = false)
private final String firstName;
#Column(name = "Last_Name", nullable = false)
private final String lastName;
public Person(String firstName, String lastName) {
this.firstName = firstName;
this.lastName = lastName;
}
}
Init (Main class):
package com.gmail.physicistsarah.gradletestproject.core;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import org.hibernate.Session;
import org.hibernate.Transaction;
public class Init {
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
EntityManagerFactory factory = Persistence.createEntityManagerFactory("Test_Project");
EntityManager manager = factory.createEntityManager();
Session session = manager.unwrap(Session.class);
Transaction transaction = session.getTransaction();
transaction.begin();
session.saveOrUpdate(new Person("Carl", "Gauss"));
session.saveOrUpdate(new Person("Benoit", "Mandelbrot"));
transaction.commit();
factory.close();
}
}

You should try using HibernatePersistenceProvider and remove the <class> element from the persistence.xml.
Also remove <exclude-unlisted-classes> since it is not applicable to Java SE persistence units as per the official schema definition http://www.oracle.com/webfolder/technetwork/jsc/xml/ns/persistence/persistence_2_1.xsd
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd ">
<persistence-unit name="Test_Project" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
<shared-cache-mode>ALL</shared-cache-mode>
<validation-mode>AUTO</validation-mode>
<properties>
<property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver" />
<property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/test_project_db?zeroDateTimeBehavior=convertToNull" />
<property name="javax.persistence.jdbc.user" value="root" />
<property name="javax.persistence.jdbc.password" value="" />
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect" />
</properties>
</persistence-unit>
</persistence>
I noticed that you are inter mixing JPA code with Hibernate code. If you're using JPA then try to stick to JPA.
Use the following code after creating the EntityManager:
EntityTransaction tran = manager.getTransaction();
tran.begin();
try {
Person savedPerson1 = manager.merge(new Person("Carl", "Gauss"));
Person savedPerson2 = manager.merge(new Person("Benoit", "Mandelbrot"));
tran.commit();
} catch (Exception e) {
tran.rollback();
}
manager.close();
factory.close();
Remember to access the returned entity from EntityManager.merge() call to access any auto-generated fields.
You should use the following Maven POM dependencies for the above to work as expected in a Java SE environment:
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>4.3.8.Final</version>
</dependency>
<dependency>
<groupId>org.hibernate.javax.persistence</groupId>
<artifactId>hibernate-jpa-2.1-api</artifactId>
<version>1.0.0.Final</version>
</dependency>

JPQL JPA access google datastore

My entity class :
public class ACCOUNT implements Serializable{
private static final long serialVersionUID = 1L;
#Id
#Column(name = "USERNAME")
private String Username;
#Column(name = "PASSWORD")
private String Password;
public ACCOUNT(String user,String pass)
{
this.Username=user;
this.Password=pass;
}
// geter and setter
my persistence.xml
<?xml version="1.0" encoding="UTF-8" ?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" version="1.0">
<persistence-unit name="transactions-optional">
<provider>org.datanucleus.api.jpa.PersistenceProviderImpl</provider>
<class>com.materialshop.server.Datastore.ACCOUNT</class>
<exclude-unlisted-classes/>
<properties>
<property name="datanucleus.NontransactionalRead" value="true"/>
<property name="datanucleus.NontransactionalWrite" value="true"/>
<property name="datanucleus.nontx.atomic" value="true"/>
<property name="datanucleus.ConnectionURL" value="appengine"/>
</properties>
</persistence-unit>
</persistence>
Now persist account and it was successful
ACCOUNT ac=new ACCOUNT("admin","123");
em.persist(ac);
I checked
http://localhost:8888/_ah/admin
and yes ,there is ACOUNT entity with 1 record admin and 123
but when I use JPQL to get all entity , it returned null
Query q=new Query("SELECT ac FROM ACCOUNT ac");
List<ACCOUNT> list=q.getResultList();
even with
em.find(ACCOUNT.class,"admin");
return null too
Did i miss something ? Please help me , very grateful for your help

Simple JPA to Postgresql 9.1 HibernateEx

Seems like a simple enough thing. I've used Hibernate sequences to MySQL and Oracle in the past but now using JPA2/Hibernate4 to Postgresql 9.1 and keep getting exceptions. Any ideas? I've tried different flavors of GenerationType.SEQUENCE and GenerationType.AUTO but nothing works. I definitely need help.
[1] Postgresql 9.1 DDL
-- removed CACHE 100
create sequence my_seq INCREMENT 1 MINVALUE 1 MAXVALUE 2147483647 START 1;
create table my_table (
id integer NOT NULL DEFAULT nextval('my_seq'),
ident text NOT NULL CONSTRAINT ident_uniq UNIQUE,
cname text NOT NULL,
created timestamp WITH TIME ZONE NOT NULL DEFAULT ('now'::text)::timestamp(6) with time zone,
lastmodified timestamp WITH TIME ZONE NOT NULL DEFAULT ('now'::text)::timestamp(6) with time zone,
CONSTRAINT my_table_pkey PRIMARY KEY(id)
);
insert into my_table (ident, cname) values ('test001', 'Test 001');
[2] Persistence.xml
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
version="2.0" >
<persistence-unit name="MyPersistenceUnit" transaction-type="RESOURCE_LOCAL">
<description>Persistence unit</description>
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<properties>
<property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect"/>
<property name="javax.persistence.jdbc.driver" value="org.postgresql.Driver" />
<property name="javax.persistence.jdbc.url" value="jdbc:postgresql://localhost:5432/mydb" />
<property name="javax.persistence.jdbc.user" value="user" />
<property name="javax.persistence.jdbc.password" value="password" />
<property name="hibernate.hbm2ddl.auto" value="validate"/>
<property name="hibernate.show_sql" value="false" />
<property name="hibernate.format_sql" value="false" />
<property name="prefer_sequence_per_entity" value="true" />
</properties>
</persistence-unit>
</persistence>
[3] Entity code
package com.mypackage;
import java.sql.Timestamp;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.SequenceGenerator;
import javax.persistence.Transient;
#Entity(name="my_table")
public class MyTable {
#SequenceGenerator(name="foo", sequenceName="my_seq", allocationSize=1, initialValue=1)
#GeneratedValue(strategy = GenerationType.IDENTITY, generator = "foo")
#Id
#Column(name = "id")
private long id;
private String ident;
private Timestamp created;
private Timestamp lastmodified;
}
[5] JUnit
public class Test_MyTable {
#Test
public void test_1() {
EntityManagerFactory emf = Persistence.createEntityManagerFactory("MyPersistenceUnit");
EntityManager em = emf.createEntityManager();
List<MyTable> list = em.createQuery("from my_table", MyTable.class).getResultList();
int size = ( (list == null) || (list.size() <= 0) ) ? 0 : list.size();
if (size == 0) {
System.out.println("Didn't find any MY_TABLE records");
} else {
System.out.println("Found [" + size + "] MY_TABLE records");
}
em.close();
emf.close();
}
}
[3] Exception
javax.persistence.PersistenceException: [PersistenceUnit: MyPersistenceUnit] Unable to build EntityManagerFactory
Caused by: org.hibernate.HibernateException: Wrong column type in public.my_table for column id. Found: serial, expected: int8

Change
#GeneratedValue(strategy = GenerationType.IDENTITY, generator = "foo")
to
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "foo")
else it won't use a sequence strategy, but an identity strategy.
And try to remove the default value of the PK column, and to define the column as bigint, since int is only 4 bytes and Java longs have 8 bytes.

EclipseLink JPA Object is not a known entity type

I have a strange problem with eclipseLink and an object which I want to persist. I have one Object (KeypointListImpl) that stores another object KeypointImpl in a List. Persisting a keypointImpl objects works great but if I try to persist a keypointListImpl object I get an java.lang.IllegalArgumentException that says the object keypointImpl isn't a known entity type.
Here is the KeypointImpl Code:
#Entity
#Table(name="Keypoints")
public class KeypointImpl implements Keypoint {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
#Enumerated(EnumType.STRING)
private DetectorType keypointType;
private float x;
private float y;
private float size;
private float angle;
private float response;
private int octave;
private int classId;
...
}
Here is the KeypointListImpl Code:
#Entity
#Table(name="KeypointLists")
public class KeypointListImpl implements KeypointList {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
#OneToOne(cascade={CascadeType.ALL}, targetEntity=KeypointImpl.class)
private List<Keypoint> keypoints;
...
}
Here is the mains content:
Keypoint kp1 = new KeypointImpl(DetectorType.FAST, 5, 5, 10, 90, 2, 3, 0);
Keypoint kp2 = new KeypointImpl(DetectorType.FAST, 6, 6, 3, 45, 1, 2, 1);
em.persist(kp1);
em.persist(kp2);
List<Keypoint> keypoints = new ArrayList<Keypoint>();
keypoints.add(kp1);
keypoints.add(kp2);
KeypointList keypointlist = new KeypointListImpl();
keypointlist.setKeypointList(keypoints);
em.persist(keypointlist);
The tables that are constructed look fine. I get a KeypointsLists(ID, KEYPOINTS_ID) and a Keypoints(..., ...) table.
Can anyone point me to my error please?! :-)
As requested the persistence.xml as well
<?xml version="1.0" encoding="UTF-8" ?>
<persistence xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
version="2.0" xmlns="http://java.sun.com/xml/ns/persistence">
<persistence-unit name="AudiModelRecognition" transaction-type="RESOURCE_LOCAL">
<class>amr.model.KeypointImpl</class>
<class>amr.model.KeypointListImpl</class>
<properties>
<property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver" />
<property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/amr" />
<property name="javax.persistence.jdbc.user" value="arm" />
<property name="javax.persistence.jdbc.password" value="..." />
<!-- EclipseLink should create the database schema automatically -->
<property name="eclipselink.ddl-generation" value="create-tables" />
<property name="eclipselink.ddl-generation.output-mode" value="database" />
</properties>
</persistence-unit>
</persistence>

Than I'll write my comment as an answer: #OneToOne on List looks wrong. Use #OneToMany.