休眠值分为两列。如何绘制地图?

当您使用hibernate本机API和hbm.xml版它仍然是这样工作的:

    <property name="dateMitUltimo" type="org.UTDateUltimo">
        <column name="DAT_ULTIMO" />
        <column name="SL_ULTIMO" />
    </property>

使用这样的用户类型:

public class UTDateUltimo
    implements CompositeUserType {

使用hibernate的JPA-API,这不再有效:-(

<entity class="de.parcit.base.db.jpa.TestEmbedded" name="TestEmbedded">
    <table name="TEMBED" />

    <attributes>
        <!-- domain="ID" type="long" -->
        <id name="id" type="long">
            <!-- <generated-value strategy="TABLE" /> -->
        </id>

        <embedded name="dateMitUltimo" />

    </attributes>
</entity>

<embeddable class="de.parcit.base.db.jpa.DateJPA" access="FIELD">

    <convert converter="de.parcit.base.db.jpa.DateConverter" attribute-name="date" />

    <attributes>

        <!-- domain="Datum_Ultimo" -->
        <basic name="date">
            <column name="DAT_ULTIMO" />
        </basic>

        <!-- domain="SL_SI" -->
        <basic name="month">
            <column name="SL_ULTIMO" />
        </basic>
    </attributes>
</embeddable>

和

public class DateConverter
    implements AttributeConverter<Date, java.sql.Date> {

更新:

“embedded”也可以与注释一起使用。 Java - JPA @Basic and @Embedded annotations

this article JPA和Hibernate将每个实体属性映射到数据库列。但是您可以使用一个小的解决方案来实现请求的映射。

首先需要2个实体属性来映射2个数据库列。如果使用基于字段的访问(注释属性而不是setter),则可以跳过这些属性的getter和setter方法。然后,您可以添加第三个属性,即您将在业务代码中使用的属性。你需要用 @Transient 并根据其他2个属性计算其值。

下面是一个映射,它使用这种方法将时间(postedAtTime)和日期(posteDate)列映射到 LocalDateTime postedAt 属性。

@Entity
public class Review {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    private String comment;

    private LocalDate postedAtDate;

    private LocalTime postedAtTime;

    @Transient
    private LocalDateTime postedAt;

    public Long getId() {
        return id;
    }

    public String getComment() {
        return comment;
    }

    public void setComment(String comment) {
        this.comment = comment;
    }

    public LocalDateTime getPostedAt() {
        if (postedAt == null) {
            this.postedAt = LocalDateTime.of(this.postedAtDate, this.postedAtTime);
        }
        return postedAt;
    }

    public void setPostedAt(LocalDateTime postedAt) {
        this.postedAt = postedAt;
        this.postedAtDate = postedAt.toLocalDate();
        this.postedAtTime = postedAt.toLocalTime();
    }
}

请注意,您需要使用 postedAtDate 和 postedAtTime Review 实体对象,你不需要知道这两个内部属性。

private LocalDate tradeDate;
private LocalTime tradeTime;

public Calendar getMyTradeDateTime(){
    LocalDateTime dateTime = LocalDateTime.of(this.tradeDate, this.tradeTime);
    Calendar c = Calendar.getInstance();
    return c.setTimeInMillis(dateTime.toEpochSecond(ZoneOffset.of("-03:00"))*1000);
}

PS:设置虚拟机时区的zoneoffset。可以通过编程方式获取(?)。

public void setMyTradeDateTime(Calendar c) {
   LocalDateTime dateTime = LocalDateTime.ofInstant(c.toInstant(), ZoneId.systemDefault());
    this.tradeDate = dateTime.toLocalDate();
    this.tradeTime = dateTime.toLocalTime();
}

@Entity
public class Review {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    private String comment;

    private LocalDate postedAtDate;

    private LocalTime postedAtTime;

    @Transient
    private LocalDateTime postedAt;

    public Long getId() {
        return id;
    }

    public String getComment() {
        return comment;
    }

    public void setComment(String comment) {
        this.comment = comment;
    }

    public LocalDateTime getPostedAt() {
        if (postedAt == null) {
            this.postedAt = LocalDateTime.of(this.postedAtDate, this.postedAtTime);
        }
        return postedAt;
    }

    public void setPostedAt(LocalDateTime postedAt) {
        this.postedAt = postedAt;
        this.postedAtDate = postedAt.toLocalDate();
        this.postedAtTime = postedAt.toLocalTime();
    }
}