JPA-Compound-Primärschlüssel mit @EmbededId

Question

Ziel: Um eine @Entity, wo die ID ist eine zusammengesetzte Primärschlüssel mit @Embeveted.

Problem: Aufgrund meiner aktuellen Implementierung, erhalte ich folgendes Ergebnis:

[ 
    { 
    "id": 1, 
    "name": "Recipe 1", 
    "instruction": "Test Instruction", 
    "note": "Note 1", 
    "show": true, 
    "createDate": null, 
    "modify_date": null, 
    "ingredient": [ 
     {}, 
     {} 
    ] 
    } 
] 

aber ich möchte diese haben: zu

[ 
    { 
    "id": 1, 
    "name": "Recipe 1", 
    "instruction": "Test Instruction", 
    "note": "Note 1", 
    "show": true, 
    "createDate": null, 
    "modify_date": null, 
    "ingredient": [ 
     {ingredient_id: 1, 
     amount: 10}, 
     {ingredient_id: 2, 
     amount: 20} 
    ] 
    } 
] 

Kann jemand bitte helfen Sie mir zu sehen, Ich habe in meiner recipeIngredient Klasse falsch gemacht? Danke im Voraus.

Die folgenden sind meine Implementierung:

Das Schema:

RecipeIngredientId.java

@Embeddable 
public class RecipeIngredientId implements Serializable { 
    @Column(name = "recipe_id", nullable = false) 
    private int recipeId; 

    @Column(name = "ingredient_id", nullable = false) 
    private int ingredientId; 

    public RecipeIngredientId() {} 

    public RecipeIngredientId(int recipeId, int ingredientId) { 
     this.recipeId = recipeId; 
     this.ingredientId = ingredientId; 
    } 
} 

RecipeIngredient.java

@Entity 
@Table(name = "recipe_ingredient") 
public class RecipeIngredient implements Serializable 
{ 
    @EmbeddedId 
    private RecipeIngredientId id; 

    @ManyToOne 
    @JoinColumn(name="ingredient_id", insertable = false, updatable = false) 
    private Ingredient ingredient; 
    @ManyToOne 
    @JoinColumn(name = "recipe_id", insertable = false, updatable = false) 
    private Recipe recipe; 
    private double amount; 

    public RecipeIngredient() {} 

    public RecipeIngredient(Recipe recipe, Ingredient ingredient, double amount){ 
     this.recipe = recipe; 
     this.ingredient = ingredient; 
     this.amount = amount; 
    } 
} 

Recipe.java:

@Entity 
public class Recipe { 
    private int id; 

    @NotNull 
    private String name; 

    private String instruction; 
    private String note; 

    @NotNull 
    private boolean show; 

    @CreationTimestamp 
    @Temporal(TemporalType.DATE) 
    @Column(name = "create_date") 
    private Date createDate; 

    @UpdateTimestamp 
    @Temporal(TemporalType.TIMESTAMP) 
    @Column(name = "modify_date") 
    private Date modify_date; 

    private Set<RecipeIngredient> recipeIngredients; 

    public Recipe() {} 

    public Recipe(String name, String instruction, String note, boolean show) { 
     this.name = name; 
     this.instruction = instruction; 
     this.note = note; 
     this.show = show; 
    } 

    @Id 
    @GeneratedValue(strategy = GenerationType.AUTO) 
    public int getId() { 
     return id; 
    } 

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

    public String getName() { 
     return name; 
    } 

    public void setName(String name) { 
     this.name = name; 
    } 

    public String getInstruction() { 
     return instruction; 
    } 

    public void setInstruction(String instruction) { 
     this.instruction = instruction; 
    } 

    public String getNote() { 
     return note; 
    } 

    public void setNote(String note) { 
     this.note = note; 
    } 

    public boolean isShow() { 
     return show; 
    } 

    public void setShow(boolean show) { 
     this.show = show; 
    } 

    public Date getCreateDate() { 
     return createDate; 
    } 

    public void setCreateDate(Date createDate) { 
     this.createDate = createDate; 
    } 

    public Date getModify_date() { 
     return modify_date; 
    } 

    public void setModify_date(Date modify_date) { 
     this.modify_date = modify_date; 
    } 

    @OneToMany(mappedBy = "recipe", cascade = CascadeType.ALL) 
    public Set<RecipeIngredient> getIngredient() { 
     return recipeIngredients; 
    } 

    public void setIngredient(Set<RecipeIngredient> recipeIngredients) { 
     this.recipeIngredients = recipeIngredients; 
    } 
} 

Ingredient.java

@Entity 
public class Ingredient { 
    private int id; 

    @NotNull 
    @Column(unique=true) 
    private String name; 

    private Set<RecipeIngredient> recipeIngredients; 

    public Ingredient() {} 

    public Ingredient(String name) { 
     this.name = name; 
    } 

    @Id 
    @GeneratedValue(strategy = GenerationType.AUTO) 
    public int getId() { 
     return id; 
    } 

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

    public String getName() { 
     return name; 
    } 

    public void setName(String name) { 
     this.name = name; 
    } 

    @OneToMany(mappedBy = "ingredient", cascade = CascadeType.ALL) 
    public Set<RecipeIngredient> getRecipeIngredients() { 
     return recipeIngredients; 
    } 

    public void setRecipeIngredients(Set<RecipeIngredient> recipeIngredients) { 
     this.recipeIngredients = recipeIngredients; 
    } 
} 

Answer 1

Dies ist ein Fall von "abgeleiteter Identität". RecipeIngredient sollte wie folgt aussehen:

@Entity 
@Table(name = "recipe_ingredient") 
public class RecipeIngredient implements Serializable 
{ 
    @EmbeddedId 
    private RecipeIngredientId id; 

    @MapsId("ingredientId") // maps ingredientId attribute of embedded id 
    @ManyToOne 
    @JoinColumn(name="ingredient_id", insertable = false, updatable = false) 
    private Ingredient ingredient; 

    @MapsId("recipeId") // maps recipeId attribute of embedded id 
    @ManyToOne 
    @JoinColumn(name = "recipe_id", insertable = false, updatable = false) 
    private Recipe recipe; 
    private double amount; 

    public RecipeIngredient() {} 

    public RecipeIngredient(Recipe recipe, Ingredient ingredient, double amount){ 
     this.recipe = recipe; 
     this.ingredient = ingredient; 
     this.amount = amount; 
    } 
} 

Beachten Sie die MapsId Anmerkungen auf den beiden Feldern, deren Primärschlüssel bilden die zusammengesetzten Schlüssel abzugeben.

Abgeleitete Identitäten werden in der JPA 2.1 Spezifikation in Abschnitt 2.4.1 diskutiert.