JPA多对多关系：无法插入生成的表

Question

我有 2 个实体“Entre”和“Emplacement”：

@Entity
@Table(name = "ENTREE")
public class Entree {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "ID_ENTREE", updatable = false, nullable = false)
private long idEntree;

@Column(name = "NUM_DECLARATION", insertable=true, updatable=true, nullable=true)
private String numDeclaration;


@Column(name = "DATE_ENTREE", insertable=true, updatable=true, nullable=true)
private String dateEntree;

@Column(name = "TYPE_ENTREE",  insertable=true, updatable=true, nullable=true)
private String typeEntree;

@Column(name = "NOM_ARTICLE",  insertable=true, updatable=true, nullable=true)
private String nomArticle;

@Column(name = "TYPE_ARTICLE",  insertable=true, updatable=true, nullable=true)
private String typeArticle;

@Column(name = "QUANTITE_ENTREE",  insertable=true, updatable=true, nullable=true)
private int quantiteEntree;

@ManyToOne
@JoinColumn(name="idDossier", nullable=false)
private Dossier dossier;

 @ManyToMany( fetch = FetchType.LAZY, cascade = CascadeType.PERSIST)
 @JoinTable(name = "entree_emplacement",
 joinColumns = {
         @JoinColumn(name = "id_entree", referencedColumnName = "id_entree",
                 nullable = false, updatable = false)},
 inverseJoinColumns = {
         @JoinColumn(name = "id_emplacement", referencedColumnName = "id_emplacement",
                 nullable = false, updatable = false)})
 private Set<Emplacement> emplacement = new HashSet<>();

public Entree() {
    super();
}

public Entree( String numDeclaration, String dateEntree, String typeEntree, String nomArticle, String typeArticle, int quantiteEntree,  boolean isDone) {
    super();
    this.numDeclaration = numDeclaration;
    this.dateEntree = dateEntree;
    this.typeEntree = typeEntree;
    this.nomArticle = nomArticle;
    this.typeArticle = typeArticle;
    this.quantiteEntree = quantiteEntree;   
    
}

public long getIdEntree() {
    return idEntree;
}

public void setIdEntree(long idEntree) {
    this.idEntree = idEntree;
}


public String getNumDeclaration() {
    return numDeclaration;
}

public void setNumDeclaration(String numDeclaration) {
    this.numDeclaration = numDeclaration;
}


public String getDateEntree() {
    return dateEntree;
}

public void setDateEntree(String dateEntree) {
    this.dateEntree = dateEntree;
}

public String getTypeEntree() {
    return typeEntree;
}

public void setTypeEntree(String typeEntree) {
    this.typeEntree = typeEntree;
}

public String getNomArticle() {
    return nomArticle;
}

public void setNomArticle(String nomArticle) {
    this.nomArticle = nomArticle;
}

public String getTypeArticle() {
    return typeArticle;
}

public void setTypeArticle(String typeArticle) {
    this.typeArticle = typeArticle;
}

public int getQuantiteEntree() {
    return quantiteEntree;
}

public void setQuantiteEntree(int quantiteEntree) {
    this.quantiteEntree = quantiteEntree;
}


public Dossier getDossier() {
    return dossier;
}
public void setDossier(Dossier dossier) {
    this.dossier = dossier;
}

 public Set<Emplacement> getEmplacements() {
        return emplacement;
    }
 
 public void addEmplacement(Emplacement emplacement) {
        this.emplacement.add(emplacement);
        emplacement.getEntrees().add(this);
    }
 
    public void removeEmplacement(Emplacement emplacement) {
        this.emplacement.remove(emplacement);
        emplacement.getEntrees().remove(this);
    }

}

这里是第二个实体：

@Entity
@Table(name = "EMPLACEMENT")
public class Emplacement {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "ID_EMPLACEMENT", updatable = false, nullable = false)
private long idEmplacement;

@Column(name = "NUM_EMPLACEMENT",  insertable=true, updatable=true, nullable=false)
private String numEmplacement;

@ManyToMany(mappedBy = "emplacement", fetch = FetchType.LAZY, cascade = {CascadeType.ALL})
private Set<Entree> entree = new HashSet<>();
    

public Emplacement() {
}



public Emplacement( String numEmplacement) {
    this.numEmplacement = numEmplacement;       
}
 
public long getIdEmplacement() {
    return idEmplacement;
}

public void setIdEmplacement(long idEmplacement) {
    this.idEmplacement = idEmplacement;
}

public String getNumEmplacement() {
    return numEmplacement;
}

public void setNumEmplacement(String numEmplacement) {
    this.numEmplacement = numEmplacement;
}


public Set<Entree> getEntrees() {
    return entree;
}

}

这是我的插入代码：

@PostMapping("/ajouterEntree")
public ResponseEntity<String> addEntree(@Valid Entree entree, BindingResult result,ModelMap modelMap, @RequestParam(name = "numDossier") String numDossier, @RequestParam(name = "emplacement") String liste_emplacements) {

Emplacement e = new Emplacement(liste_emplacements);
                
                
                entree.getEmplacements().add(e);
                
                entreeService.saveEntree(entree);
                
                return new ResponseEntity<String>("ok" + result, HttpStatus.OK);
            }
      

我可以将数据插入到 Entree 和 Emplacement 表中，但是生成的第三个名为 entree-emplacement 的表是空的。

那么如何在@ManyToMany 关系中将数据插入到生成的表中？ 谢谢

Answer 1

好的，解决了。这是我的代码：

if(!liste_emplacements.equals(""))
            {
                List<String> list = new ArrayList<String>(Arrays.asList(liste_emplacements.split(",")));
                Emplacement[] emp = new Emplacement[list.size()];
                for (int i=0; i<list.size() ;i++)
                 {
                     emp[i] = new Emplacement(Long.parseLong(list.get(i)));
                     entree.getEmplacements().add(emp[i]);
                     emp[i].getEntrees().add(entree);

                 }
            }
            
            entreeService.saveEntree(entree);
            return new ResponseEntity<String>("ok" + result, HttpStatus.OK);