Hibernate：通過持久屬性的反射訪問字段 [private java.lang.Integer] 時出錯

Question

當我嘗試獲取實體屬性時，我遇到了奇怪的問題：

Hibernate: 
    select
        tarifklsk0_.ID as ID1_12_0_,
        tarifklsk0_.FK_TARIF as FK_TARIF2_12_0_,
        tarifservp1_.FK_TARIF as FK_TARIF2_11_1_,
        tarifservp1_.ID as ID1_11_1_,
        tarifservp1_.ID as ID1_11_2_,
        tarifservp1_.FK_TARIF as FK_TARIF2_11_2_,
        tarifservp1_.N1 as N3_11_2_ 
    from
        TR.TARIFXKLSK tarifklsk0_ 
    left outer join
        TR.TARIF_SERV_PROP tarifservp1_ 
            on tarifklsk0_.FK_TARIF=tarifservp1_.FK_TARIF 
    where
        tarifklsk0_.ID=?
Jun 13, 2016 7:38:26 AM org.hibernate.event.internal.DefaultLoadEventListener doOnLoad
INFO: HHH000327: Error performing load command : org.hibernate.property.access.spi.PropertyAccessException: Error accessing field [private java.lang.Integer TarifKlsk.fkTarif] by reflection for persistent property [TarifKlsk#fkTarif] : 1027303
Exception in thread "main" org.hibernate.property.access.spi.PropertyAccessException: Error accessing field [private java.lang.Integer TarifKlsk.fkTarif] by reflection for persistent property [TarifKlsk#fkTarif] : 1027303
    at org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:43)
    ....skipped...
Caused by: java.lang.IllegalArgumentException: Can not set java.lang.Integer field TarifKlsk.fkTarif to java.lang.Integer
    at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:167)
    at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:171)       

我的實體：

關稅

import java.util.HashSet;
import java.util.Set;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;
import javax.persistence.Table;

import org.hibernate.annotations.BatchSize;

@SuppressWarnings("serial")
@Entity
@Table(name = "TARIFXKLSK", schema="TR")
public class TarifKlsk implements java.io.Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "ID", updatable = false, nullable = false)
    private Integer id;

    @OneToMany(fetch = FetchType.EAGER)
    @JoinColumn(name="FK_TARIF", referencedColumnName="FK_TARIF")
    @BatchSize(size = 50)
    private Set<TarifServProp> tarifservprop = new HashSet<TarifServProp>(0);

    @Column(name = "FK_TARIF", updatable = false, nullable = false)
    private Integer fkTarif;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public Set<TarifServProp> getTarifservprop() {
        return tarifservprop;
    }

    public void setTarifservprop(Set<TarifServProp> tarifservprop) {
        this.tarifservprop = tarifservprop;
    }

    public Integer getFkTarif() {
        return fkTarif;
    }

    public void setFkTarif(Integer fkTarif) {
        this.fkTarif = fkTarif;
    }

}

關稅服務支持

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@SuppressWarnings("serial")
@Entity
@Table(name = "TARIF_SERV_PROP", schema="TR")
public class TarifServProp implements java.io.Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "ID", updatable = false, nullable = false)
    private Integer id;

    @Column(name = "FK_TARIF", updatable = false, nullable = false)
    private Integer fkTarif;

    public Integer getId() {
        return id;
    }

    @Column(name = "N1", updatable = false, nullable = false)
    private Integer n1;

    public void setId(Integer id) {
        this.id = id;
    }

    public Integer getFkTarif() {
        return fkTarif;
    }

    public void setFkTarif(Integer fkTarif) {
        this.fkTarif = fkTarif;
    }

    public Integer getN1() {
        return n1;
    }

    public void setN1(Integer n1) {
        this.n1 = n1;
    }

}

我的測試模塊：

    public static void main(String[] args) {
        SessionFactory sf = HibernateUtil.getSessionFactory();
        Session sess = sf.openSession();
        sess.beginTransaction();

        TarifKlsk k2=sess.get(TarifKlsk.class, 1027303);
        for (TarifServProp t : k2.getTarifservprop()) {
             System.out.println("Tar="+t.getN1());
        }

        System.out.println("End init");

我做錯了什么？ 我已經檢查了這些實體的所有字段，並且所有字段都正確命名....

更新我的 POM.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.journaldev.hibernate</groupId>
    <artifactId>HibernateEHCacheExample</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <description>Hibernate Secondary Level Cache Example using EHCache implementation</description>

    <dependencies>
        <!-- Hibernate Core API -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>5.1.0.Final</version>
        </dependency>
        <!-- EHCache Core APIs -->
        <!-- http://mvnrepository.com/artifact/net.sf.ehcache/ehcache-core -->
        <dependency>
            <groupId>net.sf.ehcache</groupId>
            <artifactId>ehcache-core</artifactId>
            <version>2.6.11</version>
        </dependency>

        <!-- http://mvnrepository.com/artifact/org.hibernate/hibernate-ehcache -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-ehcache</artifactId>
            <version>5.2.0.Final</version>
        </dependency>

        <!-- EHCache uses slf4j for logging -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-simple</artifactId>
            <version>1.7.5</version>
        </dependency>
    </dependencies>
</project>

更新2

我發現我的子實體不包含與來自 master 的 fk_tarif 對應的 fk_tarif 的記錄......但我認為這無關緊要，為什么存在錯誤？

Answer 1

這是 5.0 和 5.1.0 版本中的錯誤https://hibernate.atlassian.net/browse/HHH-10618

Answer 2

我建議您繼續使用 hibernate 版本 4.XX 而不是版本 5，因為它不是 100% 穩定的（更多的是 2000 個問題）。

https://hibernate.atlassian.net/projects/HHH/issues/HHH-11144?filter=allopenissues

祝你好運

Answer 3

我正在使用 EAP7，其中包含 Hibernate Core {5.0.9.Final-redhat-1}

我有兩個實體：

@Entity
@Data
@EqualsAndHashCode(callSuper = true, doNotUseGetters = true)
@ToString(callSuper = true, doNotUseGetters = true)
public class Keuze extends MainTable {

@NonNull
String naam;

@Tolerate
public Keuze() {
}

}

和

@Entity
@Data
@EqualsAndHashCode(callSuper = true, doNotUseGetters = true, exclude = {"gegeven", "werkJaar", "keuze", "keuzes" })
@ToString(callSuper = true, doNotUseGetters = true, exclude = { "gegeven", "werkJaar", "keuze", "keuzes" })
public class Waarde extends MainTable {

@NonNull
@ManyToOne(optional = false, fetch = FetchType.LAZY)
Gegeven gegeven;

@NonNull
@ManyToOne(optional = false, fetch = FetchType.LAZY)
WerkJaar werkJaar;

String alfanumeriek;

Integer numeriek;

BigDecimal valuta;

@Lob
String tekst;

Boolean polair;

@OneToOne(fetch = FetchType.LAZY, cascade = CascadeType.MERGE)
Keuze keuze;

@ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.MERGE)
Set<Keuze> keuzes;

@Tolerate
public Waarde() {
}

}

它們都從這個類擴展而來：

@MappedSuperclass
@Data
@Cacheable
public abstract class MainTable {

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

@Version
Long version;

}

在 Waarde 上調用 merge 時，會拋出以下錯誤：

Caused by: org.hibernate.property.access.spi.PropertyAccessException: Error accessing field [java.lang.Long vo.cjsm.monitoring.data.schema.dynamic.main.MainTable.id] by reflection for persistent property [vo.cjsm.monitoring.data.schema.dynamic.field.Keuze#id] : Keuze(super=MainTable(id=1, version=0), naam=Leesmotivatie)
at org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:43)
at org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:223)
at org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:4601)
at org.hibernate.event.internal.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:148)
at org.hibernate.internal.SessionImpl.fireMerge(SessionImpl.java:850)
at org.hibernate.internal.SessionImpl.merge(SessionImpl.java:832)
at org.hibernate.engine.spi.CascadingActions$6.cascade(CascadingActions.java:260)
at org.hibernate.engine.internal.Cascade.cascadeToOne(Cascade.java:398)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:323)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:162)
at org.hibernate.engine.internal.Cascade.cascadeCollectionElements(Cascade.java:431)
at org.hibernate.engine.internal.Cascade.cascadeCollection(Cascade.java:363)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:326)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:162)
at org.hibernate.engine.internal.Cascade.cascade(Cascade.java:111)
at org.hibernate.event.internal.DefaultMergeEventListener.cascadeOnMerge(DefaultMergeEventListener.java:468)
at org.hibernate.event.internal.DefaultMergeEventListener.entityIsDetached(DefaultMergeEventListener.java:327)
at org.hibernate.event.internal.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:170)
at org.hibernate.event.internal.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:69)
at org.hibernate.internal.SessionImpl.fireMerge(SessionImpl.java:840)
at org.hibernate.internal.SessionImpl.merge(SessionImpl.java:822)
at org.hibernate.internal.SessionImpl.merge(SessionImpl.java:827)
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.merge(AbstractEntityManagerImpl.java:1161)
... 149 more
Caused by: java.lang.IllegalArgumentException: Can not set java.lang.Long field vo.cjsm.monitoring.data.schema.dynamic.main.MainTable.id to java.lang.String
at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:167)
at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:171)
at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:58)
at sun.reflect.UnsafeObjectFieldAccessorImpl.get(UnsafeObjectFieldAccessorImpl.java:36)
at java.lang.reflect.Field.get(Field.java:393)
at org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:39)
... 171 more

通過刪除 Lombok 的 ToString 行並通過覆蓋默認實現添加我自己的 toString 實現，錯誤消息消失了，代碼正在恢復！

現在實體看起來像這樣：

@Entity
@Data
@EqualsAndHashCode(callSuper = true, doNotUseGetters = true)
public class Keuze extends MainTable {

@NonNull
String naam;

@Tolerate
public Keuze() {
}

@Override
public String toString() {

    return getId().toString();
}

}

所以不知何故，由於未知原因 toString 方法對 hibernate 如何合並代碼有影響......不要問我如何:-) 它似乎工作。 我在網上嘗試了所有其他方法，但沒有成功！

希望這對其他人有幫助！

Answer 4

從 Hibernate 4 升級到 5 后，我遇到了同樣的錯誤。此時，hibernate 錯誤似乎沒有在 5.3 之前的任何版本中得到修復。 在我的例子中，這個錯誤發生在使用來自 A 的屬性而不是主鍵（我知道，不是一個好的關系模型）懶惰地獲取實體 A 的集合時，該集合與 B 具有急切的一對多關系。 它實際上可能是一個比這更復雜的邊緣情況，但我現在沒有時間在最小的測試用例中重現它）。

在跟蹤 hibernate 代碼時，似乎 hibernate 在嘗試為 B 的查詢綁定參數時感到困惑，並且當它認為它試圖從對象 A 獲取外鍵時，它實際上已經具有該屬性價值。 代碼將值視為對象 A 並以上面顯示的反射錯誤結束。

通過將 B 的一對多關系更改為惰性，我能夠克服這個錯誤。 我希望這對其他人有幫助。

Answer 5

就我而言，問題是在我的模型中，setter 是自動生成的

public void setComments(List comments){
}

沒有類型。 通過將其設置為List<Comment> comments來修復它