java - Is it possible to join two entities in a specification without a relationship between them, but with a common field - Sta

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I am writing a search by fields. There are two entities between which there is only a @ManyToOne relationship. Is it possible to make a join if the root element is a DataListEntity and a specification needs to be built on its basis?

• But without creating a @OneToMany relationship in DataListEntity
• Without subqueries

    public static Specification<DataListEntity> joinWithDataListOptions() {
        return (root, query, cb) -> {
            Join<DataListEntity, DataListOptionEntity> join = root.join("join_field", JoinType.LEFT); //FIELD????
            return cb.conjunction();
        };
    }

@Entity
@Data
@Accessors(chain = true)
@Table(name = "data_list")
@FieldNameConstants
public class DataListEntity {
    @Id
    @GeneratedValue(generator = "uuid")
    private UUID id;

    @Column(name = "name")
    private String name;

    @Column(name = "description")
    private String description;

    @Column(name = "key")
    private String key;
}

Second an entity that has relationship to first entity how @ManyToOne

@Entity
@Data
@Accessors(chain = true)
@Table(name = "data_list_option")
public class DataListOptionEntity implements EasyLoggable {
    @Id
    @GeneratedValue(generator = "uuid")
    private UUID id;

    @Column(name = "data_list_id")
    private UUID dataListId;

    @Column(name = "business_account_id")
    private UUID businessAccountId;

    @Column(name = "option")
    private String option;

    @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumn(name = "data_list_id", insertable = false, updatable = false)
    private DataListEntity dataList;
}

Why do I need this? To then use the connection in the search by table fields. I don't want to make a connection for each search by field, but to use one connection and add many predicates to it, but then call the logic in other methods and connect through "and"

I am writing a search by fields. There are two entities between which there is only a @ManyToOne relationship. Is it possible to make a join if the root element is a DataListEntity and a specification needs to be built on its basis?

• But without creating a @OneToMany relationship in DataListEntity
• Without subqueries

    public static Specification<DataListEntity> joinWithDataListOptions() {
        return (root, query, cb) -> {
            Join<DataListEntity, DataListOptionEntity> join = root.join("join_field", JoinType.LEFT); //FIELD????
            return cb.conjunction();
        };
    }

@Entity
@Data
@Accessors(chain = true)
@Table(name = "data_list")
@FieldNameConstants
public class DataListEntity {
    @Id
    @GeneratedValue(generator = "uuid")
    private UUID id;

    @Column(name = "name")
    private String name;

    @Column(name = "description")
    private String description;

    @Column(name = "key")
    private String key;
}

Second an entity that has relationship to first entity how @ManyToOne

@Entity
@Data
@Accessors(chain = true)
@Table(name = "data_list_option")
public class DataListOptionEntity implements EasyLoggable {
    @Id
    @GeneratedValue(generator = "uuid")
    private UUID id;

    @Column(name = "data_list_id")
    private UUID dataListId;

    @Column(name = "business_account_id")
    private UUID businessAccountId;

    @Column(name = "option")
    private String option;

    @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumn(name = "data_list_id", insertable = false, updatable = false)
    private DataListEntity dataList;
}

Why do I need this? To then use the connection in the search by table fields. I don't want to make a connection for each search by field, but to use one connection and add many predicates to it, but then call the logic in other methods and connect through "and"

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