Insert the specify maven dependency for each implementation:

JPA:

<dependency>
	<groupId>org.objectquery</groupId>
	<artifactId>jpaobjectquery</artifactId>
	<version>1.0.0</version>
</dependency>

<dependency>
	<groupId>org.objectquery</groupId>
	<artifactId>jdoobjectquery</artifactId>
	<version>1.0.0</version>
</dependency>

<dependency>
	<groupId>org.objectquery</groupId>
	<artifactId>orientdbobjectquery</artifactId>
	<version>1.0.0</version>
</dependency>

The requirements for build a query with query builder is an java Object Oriented "Domain" that is an group of persisted objects.

public class Dog {
	private String name;
	private Person owner;
	private Home home;
	...gets sets...
};

public class Person {
	private String name;
	private List<Person> friends;
	private Person mum;
	private Person dud;
	private Home home;
	private Dog dog;
	...gets sets...
}

public class Home {
	public enum HomeType {KENNEL,HOUSE};
	private String address;
	private HomeType type;
	private int weight;
	private double price;
	...gets sets...
}

Search All person that live in "rue d'anton" with a mum with name "elisabeth" and order by name.

ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
Person toSearch = query.target();
query.eq(toSearch.getHome().getAddress(),"rue d'anton");
query.eq(toSearch.getMum().getName(),"elisabeth");
query.order(toSearch.getName());

Select name and address of person.

ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
Person toSearch = query.target();
query.prj(toSearch.getName());
query.prj(toSearch.getHome().getAddress());

Count all person that live in "rue d'anton"

ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
Person toSearch = query.target();
query.prj(toSearch,ProjectionType.COUNT);
query.eq(toSearch.getHome().getAddress(),"rue d'anton");

Search all person with name elisabeth or jhon.

ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
Person toSearch = query.target();
QueryCondition or = oq.or();
or.eq(toSearch.getName(),"elisabeth");
or.eq(toSearch.getName(),"jhon");

Primitive type need a different management, for some technical reasons is not possible use primitive type directly
for use it we need to box it

ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
Person toSearch = query.target();
query.eq(query.box(toSearch.getWeight()),2);
query.eq(query.box(toSearch.getPrice()),4000.0);

Direct execute:

javax.persistence.EntityManager entityManager= ....
ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
...
List<Person> res = (List<Person>)JPAObjectQuery.execute(query, entityManager);
...

javax.persistence.EntityManager entityManager= ....
ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
...
javax.persistence.Query jpaQuery = JPAObjectQuery.buildQuery(query, entityManager);
...

ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
...
JPQLQueryGenerator jpqlGenerator = JPAObjectQuery.jpqlGenerator(query);
String jpql = jpqlGenerator.getQuery();
Map<String,Object> paramenters = jpqlGenerator.getParameters();
...

Direct execute:

javax.jdo.PersistenceManager peristenceManager= ....
ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
...
List<Person> res = (List<Person>)JDOObjectQuery.execute(query, peristenceManager);
...

ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
...
JDOQLQueryGenerator jdoqlGenerator = JDOObjectQuery.jdoqlGenerator(query);
String jpql = jdoqlGenerator.getQuery();
Map<String,Object> paramenters = jdoqlGenerator.getParameters();
...

Direct execute:

com.orientechnologies.orient.object.db.OObjectDatabaseTx db= ....
ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
...
List<Person> res = (List<Person>)OrientDBObjectQuery.execute(query, db);
...

ObjectQuery<Person> query = new GenericObjectQuery<Person>(Person.class);
...
OrientDBQueryGenerator oriendbGenerator = OrientDBObjectQuery.oriendbGenerator(query);
String orientdbql = oriendbGenerator.getQuery();
Map<String,Object> paramenters = oriendbGenerator.getParameters();
...