使用休眠注释生成数据库（未找到外键）

Question

I am trying to create OneToOne relation using Hiberate/JPA between two classes Stock and StockDetails, so when i generate the database I'm not seeing the foreign key in the StockDetail table that should reference Stock, this is my codes :

Stock Classe :

@Entity
@Table(name = "stock", catalog = "migration")
public class Stock implements java.io.Serializable {

    private Integer Stock_Id;
    private StockDetail stockDetail;

    @Id
    @GeneratedValue(strategy = IDENTITY)
    @Column(name = "Stock_Id", nullable = false)
    public Integer getStock_Id() {
        return this.Stock_Id;
    }

    @OneToOne(fetch = FetchType.LAZY, mappedBy = "stock", cascade = CascadeType.ALL)
    public StockDetail getStockDetail() {
        return this.stockDetail;
    }

}

StockDetail Classe :

@Entity
@Table(name = "detail_stock", catalog = "migration")
public class StockDetail implements java.io.Serializable {

    private Integer Stock_Id;
    private Stock stock;

    @GenericGenerator(name = "generator", strategy = "foreign", 
    parameters = @Parameter(name = "property", value = "stock"))
    @Id
    @GeneratedValue(generator = "generator")
    @Column(name = "Stock_Id", unique = true, nullable = false)
    public Integer getStock_Id() {
        return this.Stock_Id;
    }

    @OneToOne(fetch = FetchType.LAZY)
    @PrimaryKeyJoinColumn
    public Stock getStock() {
        return this.stock;
    }

}

I found one topic about the same issue, but it didn't resolve my probleme:

Why Foreign key not inserted in hibernate

Answer 1

You got to do something like this in StockDetail

@Entity
@Table(name = "detail_stock", catalog = "migration")
public class StockDetail implements java.io.Serializable {

    private Integer stockDetailId;
    private Stock stock;

    @OneToOne(fetch = FetchType.LAZY)
    public Stock getStock() {
        return this.stock;
    }

    /**
     * @param stock
     *            the stock to set
     */
    public void setStock(Stock stock) {
        this.stock = stock;
    }

    /**
     * @return the stockDetailId
     */
    @Id
    public Integer getStockDetailId() {
        return stockDetailId;
    }

    /**
     * @param stockDetailId the stockDetailId to set
     */
    public void setStockDetailId(Integer stockDetailId) {
        this.stockDetailId = stockDetailId;
    }

}

The issue with your configuration is that you are trying to make stock_id as primary key of stock_detail with the following configuration.

@Id
@GeneratedValue(generator = "generator")
@Column(name = "Stock_Id", unique = true, nullable = false)

Instead what you should do is have a stock_detail_id as primary key of stock_details. Since you have a bi-directional one-to-one mapping between both the entities hibernate will automatically generate the foreign key with above mapping.