java 非法尝试将非集合映射为 @OneToMany、@ManyToMany 或 @CollectionOfElements
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Illegal attempt to map a non collection as a @OneToMany, @ManyToMany or @CollectionOfElements
提问by henrycharles
I have one lawyer table which is having id(int) as a primary key and Country table having country_code(String ) as a primary key. I want to create third table using @JoinTable annotation in hibernate with two foreign key in it. But when I run it following error is coming. Not sure how to map one string and one int as foreign keys in third table.
我有一个以 id(int) 作为主键的律师表和以 country_code(String ) 作为主键的 Country 表。我想在 hibernate 中使用 @JoinTable 注释创建第三个表，其中有两个外键。但是当我运行它时会出现以下错误。不确定如何将一个字符串和一个 int 映射为第三个表中的外键。
Illegal attempt to map a non collection as a @OneToMany, @ManyToMany or @CollectionOfElements: com.test.common.entities.Country.lawyer
This is my code
这是我的代码
@Entity
@Table(name = "lawyer")
public class Lawyer {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "lawyer_batch_no")
private int lawyerbatchNo;
@ManyToOne(targetEntity = Country.class, cascade = { CascadeType.ALL })
@JoinTable(name = "lawyer_cscd", joinColumns = {
@JoinColumn(name = "lawyer_batch_no", referencedColumnName = "lawyer_batch_no") }, inverseJoinColumns = {
@JoinColumn(name = "country_code", referencedColumnName = "country_code") })
private Country country;
getter setter...
}
@Entity
@Table(name = "country")
public class Country {
private static final long serialVersionUID = 1L;
@Id
@Column(name = "country_code")
protected String country_code;
@Column(name = "abbreviation")
protected String abbreviation;
@Column(name = "name", nullable = false)
protected String name;
@OneToMany(cascade = CascadeType.ALL, mappedBy = "country")
protected Set<State> state = new HashSet<State>();
@OneToMany(targetEntity = Lawyer.class, cascade = { CascadeType.ALL }, orphanRemoval = true)
@JoinTable(name = "lawyer_cscd", joinColumns = {
@JoinColumn(name = "country_code", referencedColumnName = "country_code") }, inverseJoinColumns = {
@JoinColumn(name = "lawyer_batch_no", referencedColumnName = "lawyer_batch_no") })
private Lawyer lawyer;
getter setter....
}
回答by baao
The error indicates that private Lawyer lawyerneeds to be a collection as it's a @OneToManyrelationship. In the Countryclass, the last relationship should be
该错误表明它private Lawyer lawyer需要是一个集合，因为它是一个@OneToMany关系。在Country类中，最后一个关系应该是
@OneToMany(targetEntity = Lawyer.class, cascade = { CascadeType.ALL }, orphanRemoval = true)
@JoinTable(name = "lawyer_cscd", joinColumns = {
@JoinColumn(name = "country_code", referencedColumnName = "country_code") }, inverseJoinColumns = {
@JoinColumn(name = "lawyer_batch_no", referencedColumnName = "lawyer_batch_no") })
private Set<Lawyer> lawyer;
// or a Collection/List/etc.
