java - org.hibernate.AnnotationException : A Foreign key refering has the wrong number of column. 应该是 2

Question

我有上面截图中的表格

类的写法如下

@Entity  
public class Object {  
    @Id  
    private int id;  

    private String name;  

    @OneToMany(mappedBy="object",fetch=FetchType.LAZY)  
    private List<ObjectAttribute> attrubuteList;  
}  

@Entity  
public class ObjectAttribute {  
    @Id  
    private int id;  
    @Id  
    @ManyToOne  
    @JoinColumn(name="objectId")  
    private Object object;  
    private String name;  
}  

@Entity  
public class Filter {  
    @Id  
    private int filterId;  
    @ManyToOne  
    @JoinColumn(name="ObjectId")  
    private Object object;  
    private String filterName;  
    @OneToMany(mappedBy="filter")  
    private Set<FilterAttribute> filterValues;  
}  

@Entity  
public class FilterAttribute implements Serializable {  

    @Id  
    private int filterAttrId;  
    @Id  
    @ManyToOne  
    @JoinColumn(name="objectId")  
    private Object object;  
    @Id  
    @ManyToOne  
    @JoinColumn(name="filterId")  
    private Filter filter;  
    @Id  
    @ManyToOne  
    @JoinColumn(name="attributeId")  
    private ObjectAttribute attribute;  

    private String value;  
} 

注意没有添加getter和setter

测试代码如下

List<Object> list = sess.createCriteria(Object.class).list();  
        for(Object ob: list)  
        {  
            System.out.println("Object name : "+ ob.getName());  
            List<ObjectAttribute> attList = ob.getAttrubuteList();  

            for (Iterator iterator = attList.iterator(); iterator.hasNext();) {  
                ObjectAttribute objectAttribute = (ObjectAttribute) iterator  
                        .next();  
                System.out.println(objectAttribute.getName());  
            }  
        }  

我得到以下异常

Caused by: org.hibernate.AnnotationException: A Foreign key refering test.rest.ObjectAttribute from test.rest.FilterAttribute has the wrong number of column. should be 2  
    at org.hibernate.cfg.annotations.TableBinder.bindFk(TableBinder.java:450)  

我开始知道我应该在 FilterAttribute 类中有 2 个属性来保存复合键。但是我们该怎么做呢？

Answer 1

@Entity  
public class ObjectAttribute {  
    @Id  
    private int id;  
    @Id  <------------------------ try to remove this annotation
    @ManyToOne  
    @JoinColumn(name="objectId")  
    private Object object;  
    private String name;  
}  

它认为您的 ObjectAttribute 有 2 个 ids 复合键

更新:如果它真的有复合多列主键，你应该引用两列