"In the middle of the road there was a stone
had a stone in the way
had a stone
in the middle of the road there was a stone[...]" Carlos Drummond de Andrade
Joking aside, I found the reason I couldn’t make the configuration. I have made a brief step by step that will assist anyone with the same problem or those who come across the same.
INSTRUCTIONS
Create a JPA project in new > JPA Project;
Configure the fields Projectile name with the name of your project; the field Target Runtime with the version of his Rhyme; and in the field Configuration choose the option Basic JPA Configuration and click the Next button;
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On the JPA Facet screen (two screens after the JPA Project screen) you must:
- Click on Add Connection and configure a connection to your database; after that just click the Finish button;
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Ready now your JPA project is already configured and ready to generate its entities. Now just start the resource JPA Tools > Generate Entities from Tables right-clicking on the project. The result is figure below. You select the tables and the tool creates the entities already mapped for you. Amazing resource!
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The code below shows the code of the Author entity created from the author table and the relations with this table:
package model;
import java.io.Serializable;
import javax.persistence.*;
import java.util.List;
/**
* The persistent class for the autor database table.
*
*/
@Entity
@Table(name="autor")
@NamedQuery(name="Autor.findAll", query="SELECT a FROM Autor a")
public class Autor implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
private int id;
private String nome;
//bi-directional many-to-one association to AutorLivro
@OneToMany(mappedBy="autor")
private List<AutorLivro> autorLivros;
public Autor() {
}
public int getId() {
return this.id;
}
public void setId(int id) {
this.id = id;
}
public String getNome() {
return this.nome;
}
public void setNome(String nome) {
this.nome = nome;
}
public List<AutorLivro> getAutorLivros() {
return this.autorLivros;
}
public void setAutorLivros(List<AutorLivro> autorLivros) {
this.autorLivros = autorLivros;
}
public AutorLivro addAutorLivro(AutorLivro autorLivro) {
getAutorLivros().add(autorLivro);
autorLivro.setAutor(this);
return autorLivro;
}
public AutorLivro removeAutorLivro(AutorLivro autorLivro) {
getAutorLivros().remove(autorLivro);
autorLivro.setAutor(null);
return autorLivro;
}
}
References