@Entity
// @Table (name="AlternativeTableName")
public class Person implements Serializable {
  
  protected int id;
  protected String name;
  protected Date dateOfBirth;
  
  public void setId (int id) {
    this.id = id;
  }
  
  @Id(generate = GeneratorType.AUTO)
  public int getId () {
    return id;
  }
  
  public void setName (String name) {
    this.name = name;
  }
  
  // @Column (name="AlternativeColumnName")
  public String getName () {
    return name;
  }
  
  public void setDateOfBirth (Date dateOfBirth) {
    this.dateOfBirth = dateOfBirth;
  }
  
  public Date getDateOfBirth () {
    return dateOfBirth;
  }
}

@Entity
public class Person implements Serializable {

  // ... ...
  protected Resume resume;
  protected CreditCard [] cards;
  protected Address addr;
  
  // ... ...
    
  @OneToOne
  public Resume getResume () {
    return resume;
  }
  
  // ... ...
  
  @ManyToOne
  // @JoinColumn (name="MyCustomId")
  public Address getAddr () {
    return addr;
  }
  
  // ... ...
  
  @OneToMany
  public Collection <CreditCard> getCards () {
    return cards;
  }
}

@Entity
@Inheritance(discriminatorValue="C")
@DiscriminatorColumn(name="person_type")
public class Consultant extends Person {

  protected double rate;
  
  public void setRate (double rate) {
    this.rate = rate;
  }
  
  public double getRate () {
    return rate;
  }
}

<entity-manager>
  <name>cal</name>
  <jta-data-source>java:/DefaultDS</jta-data-source>
  <properties>
    <property name="hibernate.dialect"  
            value="org.hibernate.dialect.MySQLDialect" />
    <property name="hibernate.cache.provider_class"
            value="org.jboss.ejb3.entity.TreeCacheProviderHook"/>
    <property name="hibernate.treecache.mbean.object_name"
            value="jboss.cache:service=EJB3EntityTreeCache"/>
  </properties>
</entity-manager>

@Stateless
public class ManagerBean implements Manager {

  @PersistenceContext (unitName="cal")
  protected EntityManager em;
  
  // Use "em" 
// 使用“em”
  // ... ...
}

Person p = new Person ();
p.setName ("A new baby");
p.setDateOfBirth (new Date ());
em.persist (p);

Collection <Person> persons = (Collection <Person>) 
    em.createQuery("from Person p").getResultList();

Person p = em.find(Person.class, personId);
p.setName ("Another Name");

InputStream in; 
// 初始化輸入流
Person p = Util.deserialize (in);

// ... ...
em.merge (p);

// p現(xiàn)在是一個(gè)可管理的對(duì)象了。p的任何改變將會(huì)被自動(dòng)檢測(cè)并持久化
p.setName ("Another Name");

@TransactionAttribute(TransactionAttributeType.REQUIRESNEW)
public void update () {

// 這個(gè)方法更新Person對(duì)象
// 更新將會(huì)在這個(gè)方法的末尾被提交和刷新到數(shù)據(jù)庫(kù)中

（出處：http://m.survivalescaperooms.com）