Evitando classes anemicas

Programação Java
#1

Olá Pessoal,

bom estou brincando um pouco com JPA. Porém eu queria ficar evitando de criar classes anemicas que serão as VO e queria trabalhar mais pensando na OO.
Então montei minhas classes assim:

[code]
@Entity
@Table(name=“persons”)
@Inheritance (strategy=InheritanceType.JOINED)
public class Person {

@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE)
private Long id;
@Column
private String name;
@Column
private String rg;
@Column
private String email;

private Collection<Official> offial;

public Long getId() {
	return id;
}

/* Getters e Setters */ 

@OneToMany(cascade={CascadeType.ALL},mappedBy="person")
public Collection<Official> getOffial() {
	return offial;
}

public void setOffial(Collection<Official> offial) {
	this.offial = offial;
}

}[/code]

E a outra classe é a seguinte:

@Entity
@Table(name="officials")
@PrimaryKeyJoinColumn(name="id")
public class Official extends Person {
	
	private EntityManagerFactory factory;
	private EntityManager manager;
	
	public Official() {
		this.factory = Persistence.createEntityManagerFactory("company");
		this.manager = factory.createEntityManager();
	}
	
	@Column
	private BigDecimal salary;
	
	@Column
	private String department;
	
	public void add () {
		EntityTransaction transaction = manager.getTransaction();
		transaction.begin();
		manager.persist(this);
		transaction.commit();
		manager.close();
	}
	/* Getters e Setters */ 
}

Ele hega a gravar as informações na tabela persons mas a de officials ele dá o seguinte erro:

[quote][TopLink Info]: 2008.01.02 10:42:31.818–ServerSession(30432385)–TopLink, version: Oracle TopLink Essentials - 2006.8 (Build 060908)
[TopLink Info]: 2008.01.02 10:42:51.068–ServerSession(30432385)–file:/E:/Java/Company/bin-company login successful
============ VOU TENTAR GRAVAR ==============
[TopLink Warning]: 2008.01.02 10:42:52.849–UnitOfWork(3098834)–Exception [TOPLINK-4002] (Oracle TopLink Essentials - 2006.8 (Build 060908)): oracle.toplink.essentials.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: Invalid argument value: java.io.NotSerializableExceptionError Code: 0
Call:INSERT INTO officials (MANAGER, DEPARTMENT, SALARY, FACTORY, id) VALUES (?, ?, ?, ?, ?)
bind => [oracle.toplink.essentials.internal.ejb.cmp3.EntityManagerImpl@13c7378, TI, null, oracle.toplink.essentials.internal.ejb.cmp3.EntityManagerFactoryImpl@1c0f2e5, 1]
Query:InsertObjectQuery(company.vo.Official@49d67c)
Exception in thread "main" javax.persistence.RollbackException: Exception [TOPLINK-4002] (Oracle TopLink Essentials - 2006.8 (Build 060908)): oracle.toplink.essentials.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: Invalid argument value: java.io.NotSerializableExceptionError Code: 0
Call:INSERT INTO officials (MANAGER, DEPARTMENT, SALARY, FACTORY, id) VALUES (?, ?, ?, ?, ?)
bind => [oracle.toplink.essentials.internal.ejb.cmp3.EntityManagerImpl@13c7378, TI, null, oracle.toplink.essentials.internal.ejb.cmp3.EntityManagerFactoryImpl@1c0f2e5, 1]
Query:InsertObjectQuery(company.vo.Official@49d67c)
at oracle.toplink.essentials.internal.ejb.cmp3.transaction.base.EntityTransactionImpl.commit(EntityTransactionImpl.java:109)
at oracle.toplink.essentials.internal.ejb.cmp3.transaction.EntityTransactionImpl.commit(EntityTransactionImpl.java:45)
at company.vo.Official.add(Official.java:41)
at company.teste.Start.main(Start.java:19)
Caused by: Exception [TOPLINK-4002] (Oracle TopLink Essentials - 2006.8 (Build 060908)): oracle.toplink.essentials.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: Invalid argument value: java.io.NotSerializableExceptionError Code: 0
Call:INSERT INTO officials (MANAGER, DEPARTMENT, SALARY, FACTORY, id) VALUES (?, ?, ?, ?, ?)
bind => [oracle.toplink.essentials.internal.ejb.cmp3.EntityManagerImpl@13c7378, TI, null, oracle.toplink.essentials.internal.ejb.cmp3.EntityManagerFactoryImpl@1c0f2e5, 1]
Query:InsertObjectQuery(company.vo.Official@49d67c)
at oracle.toplink.essentials.exceptions.DatabaseException.sqlException(DatabaseException.java:303)
at oracle.toplink.essentials.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:551)
at oracle.toplink.essentials.internal.databaseaccess.DatabaseAccessor.executeCall(DatabaseAccessor.java:437)
at oracle.toplink.essentials.internal.sessions.AbstractSession.executeCall(AbstractSession.java:675)
at oracle.toplink.essentials.internal.queryframework.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:213)
at oracle.toplink.essentials.internal.queryframework.DatasourceCallQueryMechanism.insertObject(DatasourceCallQueryMechanism.java:322)
at oracle.toplink.essentials.internal.queryframework.StatementQueryMechanism.insertObject(StatementQueryMechanism.java:176)
at oracle.toplink.essentials.internal.queryframework.StatementQueryMechanism.insertObject(StatementQueryMechanism.java:190)
at oracle.toplink.essentials.internal.queryframework.DatabaseQueryMechanism.insertObjectForWrite(DatabaseQueryMechanism.java:457)
at oracle.toplink.essentials.queryframework.InsertObjectQuery.executeCommit(InsertObjectQuery.java:74)
at oracle.toplink.essentials.internal.queryframework.DatabaseQueryMechanism.performUserDefinedWrite(DatabaseQueryMechanism.java:635)
at oracle.toplink.essentials.internal.queryframework.DatabaseQueryMechanism.performUserDefinedInsert(DatabaseQueryMechanism.java:599)
at oracle.toplink.essentials.internal.queryframework.DatabaseQueryMechanism.insertObjectForWriteWithChangeSet(DatabaseQueryMechanism.java:495)
at oracle.toplink.essentials.queryframework.WriteObjectQuery.executeCommitWithChangeSet(WriteObjectQuery.java:130)
at oracle.toplink.essentials.internal.queryframework.DatabaseQueryMechanism.executeWriteWithChangeSet(DatabaseQueryMechanism.java:283)
at oracle.toplink.essentials.queryframework.WriteObjectQuery.executeDatabaseQuery(WriteObjectQuery.java:67)
at oracle.toplink.essentials.queryframework.DatabaseQuery.execute(DatabaseQuery.java:609)
at oracle.toplink.essentials.queryframework.DatabaseQuery.executeInUnitOfWork(DatabaseQuery.java:536)
at oracle.toplink.essentials.queryframework.ObjectLevelModifyQuery.executeInUnitOfWorkObjectLevelModifyQuery(ObjectLevelModifyQuery.java:123)
at oracle.toplink.essentials.queryframework.ObjectLevelModifyQuery.executeInUnitOfWork(ObjectLevelModifyQuery.java:95)
at oracle.toplink.essentials.internal.sessions.UnitOfWorkImpl.internalExecuteQuery(UnitOfWorkImpl.java:2218)
at oracle.toplink.essentials.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:937)
at oracle.toplink.essentials.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:894)
at oracle.toplink.essentials.internal.sessions.CommitManager.commitNewObjectsForClassWithChangeSet(CommitManager.java:254)
at oracle.toplink.essentials.internal.sessions.CommitManager.commitAllObjectsWithChangeSet(CommitManager.java:175)
at oracle.toplink.essentials.internal.sessions.AbstractSession.writeAllObjectsWithChangeSet(AbstractSession.java:2638)
at oracle.toplink.essentials.internal.sessions.UnitOfWorkImpl.commitToDatabase(UnitOfWorkImpl.java:1030)
at oracle.toplink.essentials.internal.ejb.cmp3.base.RepeatableWriteUnitOfWork.commitToDatabase(RepeatableWriteUnitOfWork.java:357)
at oracle.toplink.essentials.internal.sessions.UnitOfWorkImpl.commitToDatabaseWithChangeSet(UnitOfWorkImpl.java:1112)
at oracle.toplink.essentials.internal.ejb.cmp3.base.RepeatableWriteUnitOfWork.commitRootUnitOfWork(RepeatableWriteUnitOfWork.java:82)
at oracle.toplink.essentials.internal.sessions.UnitOfWorkImpl.commitAndResume(UnitOfWorkImpl.java:842)
at oracle.toplink.essentials.internal.ejb.cmp3.transaction.base.EntityTransactionImpl.commit(EntityTransactionImpl.java:90)
… 3 more
Caused by: java.sql.SQLException: Invalid argument value: java.io.NotSerializableException
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:910)
at com.mysql.jdbc.PreparedStatement.setSerializableObject(PreparedStatement.java:3185)
at com.mysql.jdbc.PreparedStatement.setObject(PreparedStatement.java:2838)
at oracle.toplink.essentials.internal.databaseaccess.DatabasePlatform.setPrimitiveParameterValue(DatabasePlatform.java:1399)
at oracle.toplink.essentials.internal.databaseaccess.DatabasePlatform.setParameterValueInDatabaseCall(DatabasePlatform.java:1389)
at oracle.toplink.essentials.internal.databaseaccess.DatabasePlatform.setParameterValueInDatabaseCall(DatabasePlatform.java:1450)
at oracle.toplink.essentials.internal.databaseaccess.DatabasePlatform.setParameterValueInDatabaseCall(DatabasePlatform.java:1438)
at oracle.toplink.essentials.internal.databaseaccess.DatabaseCall.prepareStatement(DatabaseCall.java:608)
at oracle.toplink.essentials.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:470)
… 33 more
[/quote]

Alguém poderia me ajudar ??? Outra dúvida tem alguma annotation para que na classe official ele ignore as variaveis factory e manager … pois ele está criando como se fossem campos da minha tabela e na verdade são só para a persistencia …

Muito obrigado pessoal …

#2

Para ignorar vc coloca @transient

@Transient
String nomeSobrenome;
#3

Gosto do seu modo de pensar, o modelo deveria ser mais que um simples record ou struct como em Pascal e C respectivamente :wink:

#4

Coloquei o @transient ele não registro os campos mas o erro do printstacktrace é o mesmo mais alguém pode me ajudar …

Desculpa não entendi sua colocação … poderia me exemplificar a maneira mais correta de fazer isso!

obrigado

#5

[quote][TopLink Info]: 2008.01.02 10:42:31.818–ServerSession(30432385)–TopLink, version: Oracle TopLink Essentials - 2006.8 (Build 06090
[TopLink Info]: 2008.01.02 10:42:51.068–ServerSession(30432385)–file:/E:/Java/Company/bin-company login successful
============ VOU TENTAR GRAVAR ==============
[TopLink Warning]: 2008.01.02 10:42:52.849–UnitOfWork(3098834)–Exception [TOPLINK-4002] (Oracle TopLink Essentials - 2006.8 (Build 06090): oracle.toplink.essentials.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: Invalid argument value: java.io.NotSerializableExceptionError Code: 0
Call:INSERT INTO officials (MANAGER, DEPARTMENT, SALARY, FACTORY, id) VALUES (?, ?, ?, ?, ?) [/quote]
Ainda tenta colocar este MANAGER ?
posta o trace de novo.

#6

Eu acredito que o erro neste cenário é por falta das classes não estarem implementando a interface Serializable.

#7

até onde entendi o erro é realemnte a classe serializable

conforme erro do seu log:

 Invalid argument value: java.io.NotSerializableExceptionError Code: 0

Tente implementar na sua classe person/officina a classe Serializable

public class Person implements Serializable {

}
#8

Olá Pessoal,

Bom na verdade meu problema era só colocar o @Transient.

@Transient private EntityManagerFactory factory; @Transient private EntityManager manager;

mas eu precisava colocar para cada …

Obrigado pessoal…

#9

[quote=bdoweb]Olá Pessoal,

Bom na verdade meu problema era só colocar o @Transient.

@Transient private EntityManagerFactory factory; @Transient private EntityManager manager;

mas eu precisava colocar para cada …

Obrigado pessoal…[/quote]

Apesar que você poderia estar utilizando o pattern DAO para manipular estes entity*´s

#10

Minha dúvida é qual a vantagem de utilizar um DAO para isso?

#11

Leia a motivação da existência do pattern DAO.

#12

DAO seria para criar uma camada de acesso aos seus dados.
Mas acho que o Hibernate já é uma boa camada :slight_smile:
Normalmente as classes são anemicas como vc bem colocou, elas só representam a info do banco
Tua arquitetura
tabela -> objeto
arquitetura com o dao
banco -> dao -> pojo
onde POJO = classe anêmica

#13

O normal é utilizar um MVC que tem um DAO
usuário -> requisição -> visão -> controle -> modelo(pojo) -> DAO -> banco de dados

bom o pojo é a info do banco e ela tem que percorrer todas as camadas praticamente.

o DAO que se encarrega de passar a info do banco para um objeto.

#14