查找列的Hibernate註釋

Question

我有三個表：po_dtl和workbook_types。 每個採購訂單行（po_dtl）都會有「workbook_code」列來引用workbook_types。 基本上，po_dtl.workbook_code只是workbook_types.workbook_code的查找代碼。

簡化Java類的

@Entity 
@Table(name="po_dtl") 
public class PurchaseOrderDtl { 
    @Id 
    @Column(name = "po_dtl_id") 
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "po_dtl_s") 
    @SequenceGenerator(name = "po_dtl_s", sequenceName = "po_dtl_s", allocationSize = 1, initialValue = 1) 
    private long id; 

    @Column(name = "price_base", length = 7) 
    private int priceBase; 

    // ??? What is the annotation for workbook_Types? 
    private WorkbookType workbookType; 

    .... 
} 

雖然workbook_types

@Entity 
@Table(name = "workbook_types") 
public class WorkbookType { 

    @Id 
    @Column(name = "workbook_code") 
    private String workbookCode; 

    @Column(name = "description", length = 255) 
    private String description; 

    @Column(name = "file_root_path", length = 255) 
    private String fileRootPath; 
    .... 
} 

我ussualy使用（無休眠）是：

• workbook_types.workbook_code包含字符串 「wbook_finance」 ， 「wbook_marketing」
• 每個po_dtl.workbook_code將包含「wbook_finance」或 「wbook_marketing」
• workbook_types將只包含2行具有獨特workbook_code，而po_dtl將包含許多行，但每行必須只包含「wbook_finance」或「wbook_marketing」

感謝

Answer 1

據我瞭解你的問題，你需要@ManyToOne 或者如果新workbook_type唯一在開發階段添加使用枚舉。

@Entity 
class Country { //Country Dictionary 

} 

@Entity 
class User { 
    @ManyToOne 
    private Country country; 
} 

看到How to design tables for data dictionary when using hibernate?