Erro de mapeamento com Hibernate Annotation.. ajuda

import java.io.Serializable;
import javax.persistence.*;

@Entity
@Table(name = "public.especialidade")
@SuppressWarnings("serial")
public class Especialidade implements Serializable {

    @Id
    @Column(name="id_especialidade")
    @GeneratedValue(strategy=GenerationType.AUTO)
    private Integer id;

    @Column(name="nome")
    private String nome;
   
        
    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getNome() {
        return nome;
    }

    public void setNome(String nome) {
        this.nome = nome;
    }

    
}

org.hibernate.MappingException: Unknown entity: br.com.model.Especialidade

at org.hibernate.impl.SessionFactoryImpl.getEntityPersister(SessionFactoryImpl.java:550)

at org.hibernate.impl.SessionImpl.getEntityPersister(SessionImpl.java:1338)

at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:98)

at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:187)

at org.hibernate.event.def.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:33)

at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:172)

at org.hibernate.event.def.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:27)

at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:70)

at org.hibernate.impl.SessionImpl.fireSave(SessionImpl.java:535)

at org.hibernate.impl.SessionImpl.save(SessionImpl.java:523)

at org.hibernate.impl.SessionImpl.save(SessionImpl.java:519)