命名查询和 POJO class

Question

这是我的实体：

Client
import java.io.Serializable;
import java.util.List;
import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import javax.xml.bind.annotation.XmlRootElement;

/**
 *
 * @author AMINA
 */
@Entity
@Table(name = "client")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "Client.findAll", query = "SELECT c FROM Client c"),
    @NamedQuery(name = "Client.findById", query = "SELECT c FROM Client c WHERE c.id = :id"),
    @NamedQuery(name = "Client.findByPr\u00e9nom", query = "SELECT c FROM Client c WHERE c.pr\u00e9nom = :pr\u00e9nom"),
    @NamedQuery(name = "Client.findByNom", query = "SELECT c FROM Client c WHERE c.nom = :nom"),
    @NamedQuery(name = "Client.findByT\u00e9l\u00e9phone", query = "SELECT c FROM Client c WHERE c.t\u00e9l\u00e9phone = :t\u00e9l\u00e9phone"),
    @NamedQuery(name = "Client.findByEmail", query = "SELECT c FROM Client c WHERE c.email = :email")})
public class Client implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "id")
    private Integer id;
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 10)
    @Column(name = "pr\u00e9nom")
    private String prénom;
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 10)
    @Column(name = "nom")
    private String nom;
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 13)
    @Column(name = "t\u00e9l\u00e9phone")
    private String téléphone;
    // @Pattern(regexp="[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?", message="Invalid email")//if the field contains email address consider using this annotation to enforce field validation
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 50)
    @Column(name = "email")
    private String email;
    //liste des commandes d'un client
    @OneToMany (mappedBy = "c")
   public List<Commande> commandes;
    public Client() {
    }

    public Client(Integer id) {
        this.id = id;
    }

    public Client(Integer id, String prénom, String nom, String téléphone, String email) {
        this.id = id;
        this.prénom = prénom;
        this.nom = nom;
        this.téléphone = téléphone;
        this.email = email;
    }

    public Integer getId() {
        return id;
    }

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

    public String getPrénom() {
        return prénom;
    }

    public void setPrénom(String prénom) {
        this.prénom = prénom;
    }

    public String getNom() {
        return nom;
    }

    public void setNom(String nom) {
        this.nom = nom;
    }

    public String getTéléphone() {
        return téléphone;
    }

    public void setTéléphone(String téléphone) {
        this.téléphone = téléphone;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (id != null ? id.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {

        if (!(object instanceof Client)) {
            return false;
        }
        Client other = (Client) object;
        if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "com.mycompany.exempletd.Client[ id=" + id + " ]";
    }

}

指挥官

import java.io.Serializable;
import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
import javax.xml.bind.annotation.XmlRootElement;

/**
 *
 * @author AMINA
 */
@Entity
@Table(name = "commande")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "Commande.findAll", query = "SELECT c FROM Commande c"),
    @NamedQuery(name = "Commande.findById", query = "SELECT c FROM Commande c WHERE c.id = :id")})
public class Commande implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "id")
    private Integer id;
    @ManyToOne
    private Client c;
    public Commande() {
    }

    public Commande(Integer id) {
        this.id = id;
    }

    public Integer getId() {
        return id;
    }

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

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (id != null ? id.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {

        if (!(object instanceof Commande)) {
            return false;
        }
        Commande other = (Commande) object;
        if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "com.mycompany.exempletd.Commande[ id=" + id + " ]";
    }

}

class哪里有问题

  import java.util.*;
  import javax.persistence.EntityManager;
  import javax.persistence.EntityManagerFactory;
  import javax.persistence.Persistence;
   import javax.persistence.NamedQuery;


  @NamedQuery(name = "reqSelect", query = "Select c.commandes From client c       where c.nom like :name"); //problem

 public class SaisieCommande {

static EntityManagerFactory emf = Persistence.createEntityManagerFactory("com.mycompany_ExempleTd_war_1.0-SNAPSHOTPU");
static EntityManager em = emf.createEntityManager();

@SuppressWarnings("empty-statement")
public static void main(String[] args) {
    Scanner s = null;
    List commandes;

    //saisie de nom
    System.out.println("donner un nom");
    String nom = s.next();
    //saisie la methode
    System.out.println("requête statique 1 requêtes dynamique 2");
    int choix = s.nextInt();
    if (choix == 1) {
        commandes = em.createNamedQuery("reqSelect").setParameter("name", nom).getResultList();
    } else if (choix == 2) {
        commandes = em.createQuery("Select c.commandes From client c where c.nom like :name").setParameter("name",nom).getResultList();
    }
}

}

我想让应用程序 Java 显示名称所有客户端命令

我写了这篇文章，但命名查询有问题。我是 Java EE 的初学者。

Answer 1

@NamedQuery只能用在类中，也就是@Entity。只需将您的命名查询从 SaisieCommande 移动到您的任何实体。

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