1º一個權限對象有三個字段
2º權限的三個字段了彌補該複合鍵
兩個屬性和化合物主鍵共享相同的列
所以你的問題看起來像這個
@Entity
public class Permission {
private PermissionId permissionId;
private Integer field1;
private Integer field2;
private Integer field3;
// required no-arg constructor
public Permission() {}
public Permission(Integer field1, Integer field2, Integer field3) {
this.field1 = field1;
this.field2 = field2;
this.field3 = field3;
setPermissionId(new PermissonId(Integer field1, Integer field2, Integer field3));
}
@EmbeddedId
public PermissionId getPermissionId() {
return this.permissionId;
}
@Column(name="FIELD_1", insertable=false, updatable=false)
public Integer getField1() {
return this.field1;
}
@Column(name="FIELD_2", insertable=false, updatable=false)
public Integer getField2() {
return this.field2;
}
@Column(name="FIELD_3", insertable=false, updatable=false)
public Integer getField3() {
return this.field3;
}
@Embeddable
public static class PermissionId implements Serializable {
private Integer field1;
private Integer field2;
private Integer field3;
// required no-arg constructor
public PermissionId() {}
public PermissionId(Integer field1, Integer field2, Integer field3) {
this.field1 = field1;
this.field2 = field2;
this.field3 = field3;
}
@Column(name="FIELD_1", nullable=false)
public Integer getField1() {
return this.field1;
}
@Column(name="FIELD_2", nullable=false)
public Integer getField2() {
return this.field2;
}
@Column(name="FIELD_3", nullable=false)
public Integer getField3() {
return this.field3;
}
public boolean equals(Object o) {
if(o == null)
return false;
if(!(o instanceof PermissionId))
return false;
final PermissionId other = (PermissionId) o;
if(!(getField1().equals(other.getField1())))
return false;
if(!(getField2().equals(other.getField2())))
return false;
if(!(getField3().equals(other.getField3())))
return false;
return true;
}
// requered hashcode impl
public int hashcode() {
// code goes here
}
}
}
但不要忘了
由於多個屬性共享相同的列,你必須確定其中一個作爲插入=假,可更新=假。否則,Hibernate會抱怨一些錯誤。
而且
當你有一個複合主鍵,你必須建立自己的價值觀。 Hibernate不支持自動生成複合主鍵。
但,如果你不喜歡這種方法,如上圖所示,你可以做以下的一個
@Entity
@IdClass(PermissionId.class)
public class Permission {
private Integer field1;
private Integer field2;
private Integer field3;
// required no-arg constructor
public Permission() {}
public Permission(Integer field1, Integer field2, Integer field3) {
this.field1 = field1;
this.field2 = field2;
this.field3 = field3;
}
@Id
@Column(name="FIELD_1", nullable=false)
public Integer getField1() {
return this.field1;
}
@Id
@Column(name="FIELD_2", nullable=false)
public Integer getField2() {
return this.field2;
}
@Id
@Column(name="FIELD_3", nullable=false)
public Integer getField3() {
return this.field3;
}
@Embeddable
public static class PermissionId implements Serializable {
private Integer field1;
private Integer field2;
private Integer field3;
// required no-arg constructor
public PermissionId() {}
public PermissionId(Integer field1, Integer field2, Integer field3) {
this.field1 = field1;
this.field2 = field2;
this.field3 = field3;
}
@Column(name="FIELD_1")
public Integer getField1() {
return this.field1;
}
@Column(name="FIELD_2")
public Integer getField2() {
return this.field2;
}
@Column(name="FIELD_3")
public Integer getField3() {
return this.field3;
}
public boolean equals(Object o) {
if(o == null)
return false;
if(!(o instanceof PermissionId))
return false;
final PermissionId other = (PermissionId) o;
if(!(getField1().equals(other.getField1())))
return false;
if(!(getField2().equals(other.getField2())))
return false;
if(!(getField3().equals(other.getField3())))
return false;
return true;
}
// requered hashcode impl
public int hashcode() {
// code goes here
}
}
}
問候,