Hibernate CriteriaQuery如何查找具有两个条件的整数列表

Suule 发表于 Dev

在嘴上

我有两个实体类：

@Table(name = "package")
public class Package {


    @Id
    @Column(name = "package_id", insertable = false, nullable = false)
    private Long packageId;

    @Column(name = "timestamp", nullable = false, updatable = false)
    @Temporal(TemporalType.TIMESTAMP)
    private Date timestamp;

    @Column(name = "name", nullable = false)
    private String name;

    @ManyToOne(fetch = FetchType.LAZY, optional = false)
    @JoinColumn(name = "queue_id",foreignKey=@ForeignKey(name = "package_queue_id_fk"))
    private Queue Queue;

@Column(name = "file_number", nullable = true)
private Integer fileNumber;

和

@Table(name = "queue")
public class Queue {

    @Id
    @Column(name = "queue_id", insertable = false, nullable = false)
    private Integer queue;

    @Column(name = "description", nullable = true)
    private String description;

    @Column(name = "name", nullable = false)
    private String name;

    @OneToMany(mappedBy = "Queue", fetch = FetchType.LAZY, cascade = { CascadeType.PERSIST, CascadeType.REFRESH })
    @MapKeyColumn(name = "package_id")
    private Set<Package> packages;

我想根据package.name和package.queue.queue_id找到文件编号列表

所以目前我只有一个条件（名称），它看起来像这样：

public List<Integer> getAllFileNumbers(String fileName, Integer queueId) {

    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Integer> query = cb.createQuery(Integer.class);

    Root<Package> package = query.from(package.class);
    query.select(package.get("fileNumber")).where(cb.equal(package.get("name"), fileName));

    return em.createQuery(query).getResultList();
}

任何人都可以帮助我添加另一个，除了要记住该值必须来自另一个实体。

编辑：

所以在@Leviand提示之后，我是这样的：

        Predicate filenamePred= cb.equal(package.get("name"), fileName);
        Predicate queueIdPred = cb.equal(package.get("queue_id"), queueId);

        query.select(package.get("fileNumber")).where(cb.and(filenamePred, queueIdPred ));

我收到错误消息：

Caused by: java.lang.IllegalArgumentException: Unable to locate Attribute  with the the given name [queue_id] on this ManagedType

列维安

您需要在条件中添加两个谓词（您可以将它们全部内联编写，我正在拆分，这样更清楚）or，例如：

Predicate filename= cb.equal(package.get("name"), fileName);
Predicate queueId = cb.equal(package.get("queue"), queueId);

//then use them in a or condition
query.select(root).where(cb.and(filename, queueId ));

本文收集自互联网，转载请注明来源。

如有侵权，请联系 [email protected] 删除。