Java Hibernate - IllegalArgumentException

Question

我有这两个班 - Letadlo和Letiste（飞机和（家）机场）。在使用java和hibernate将数据保存到数据库时，我得到了这个例外：

    16285 [Thread-2] ERROR org.hibernate.property.BasicPropertyAccessor - IllegalArgumentException in class: mapy.Letiste, getter method of property: id
org.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of mapy.Letiste.id
    at org.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:198)
    at org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:227)
    at org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:3876)
    at org.hibernate.persister.entity.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:3584)
    at org.hibernate.engine.ForeignKeys.isTransient(ForeignKeys.java:203)
    at org.hibernate.engine.ForeignKeys$Nullifier.isNullifiable(ForeignKeys.java:159)
    at org.hibernate.engine.ForeignKeys$Nullifier.nullifyTransientReferences(ForeignKeys.java:91)
    at org.hibernate.engine.ForeignKeys$Nullifier.nullifyTransientReferences(ForeignKeys.java:69)
    at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:310)
    at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:203)
    at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:129)
    at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:210)
    at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:195)
    at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.performSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:117)
    at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:93)
    at org.hibernate.impl.SessionImpl.fireSaveOrUpdate(SessionImpl.java:685)
    at org.hibernate.impl.SessionImpl.saveOrUpdate(SessionImpl.java:677)
    at org.hibernate.impl.SessionImpl.saveOrUpdate(SessionImpl.java:673)
    at logika.UkladaniDoDtb.run(UkladaniDoDtb.java:34)
    at java.lang.Thread.run(Thread.java:744)
Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:172)
    ... 19 more

保存部分：

        HibernateFactory.buildSessionFactory();
        Session session = HibernateFactory.openSession();

        session.beginTransaction().begin();

        for(Object o: DocasneUloziste.objektyKeSmazani){
            session.delete(o);
        }

        for (Linka l : DocasneUloziste.linky) {
            session.saveOrUpdate(l);
        }
        for (Letadlo l : DocasneUloziste.letadla) {  //this is 34 line
            session.saveOrUpdate(l);
        }
        for (Letiste d : DocasneUloziste.seznamLetist) { 
            session.saveOrUpdate(d);
        }


        session.getTransaction().commit();
        session.close();

Letadlo的xml：

 <class  name="mapy.Letiste">
    <meta attribute="class-description">Tato trida obsahuje info o domovskem letisti</meta>

    <id name="id" type="long" column="LETISTE_ID">
        <generator class="native" />
    </id>

    <property name="kodLetiste" type="string" not-null="true" length="3" column="KOD_LETISTE"/>
    <property name="mesto" type="string" not-null="true" length="35" column="MESTO" />

    <set name="obsluhaLetadel" cascade="all">
        <key column="LETISTE_ID" />
        <one-to-many class="mapy.Letadlo" />
    </set>

</class>

Letml的xml：

<class  name="mapy.Letiste">
        <meta attribute="class-description">Tato trida obsahuje info o domovskem letisti</meta>

        <id name="id" type="long" column="LETISTE_ID">
            <generator class="native" />
        </id>

        <property name="kodLetiste" type="string" not-null="true" length="3" column="KOD_LETISTE"/>
        <property name="mesto" type="string" not-null="true" length="35" column="MESTO" />

      <set name="obsluhaLetadel" cascade="all">
            <key column="LETISTE_ID" /> 
            <one-to-many class="mapy.Letadlo" />
       </set>   


    </class>

letadlo类包含我在XML中使用的getter和setter的所有变量以及没有参数的构造函数。

感谢您的任何建议！

编辑：Letiste Class

public class Letiste {
    private Long id;
    private String kodLetiste;
    private String mesto;
    private Set<Letadlo> obsluhaLetadel = new HashSet<Letadlo>();


public Letiste() {
}

public Letiste(String kodLetiste, String mesto) {
this.kodLetiste = kodLetiste;
this.mesto = mesto;
}


public String getKodLetiste() {
    return kodLetiste;
}


public void setKodLetiste(String kodLetiste) {
    this.kodLetiste = kodLetiste;
}

public String getMesto() {
    return mesto;
}


public void setMesto(String mesto) {
    this.mesto = mesto;
}

@Override
public boolean equals(Object obj) {
    if (obj == null) {
        return false;
    }
    if (getClass() != obj.getClass()) {
        return false;
    }
    final Letiste other = (Letiste) obj;
    if ((this.kodLetiste == null) ? (other.kodLetiste != null) : !this.kodLetiste.equals(other.kodLetiste)) {
        return false;
    }
    if ((this.mesto == null) ? (other.mesto != null) : !this.mesto.equals(other.mesto)) {
        return false;
    }
    return true;
}

@Override
public int hashCode() {
    int hash = 7;
    hash = 13 * hash + (this.kodLetiste != null ? this.kodLetiste.hashCode() : 0);
    hash = 13 * hash + (this.mesto != null ? this.mesto.hashCode() : 0);
    return hash;
}


public Long getId() {
    return id;
}

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

public Set<Letadlo> getObsluhaLetadel() {
    return obsluhaLetadel;
}

public void setObsluhaLetadel(Set<Letadlo> obsluhaLetadel) {
    this.obsluhaLetadel = obsluhaLetadel;
}

编辑：Letadlo Class

public class Letadlo {
    private Long id;
    private String kodLetadla;
    private String kapacita;
    private Integer dolet;
    private Set<Linka> seznamLinek = new HashSet<Linka>();
    private String letiste;

    public Letadlo() {
    }

    public Letadlo(String kodLetadla, String kapacita , Integer dolet, String letiste) {
    this.kodLetadla = kodLetadla;
    this.kapacita = kapacita;
    this.dolet = dolet;
    this.letiste = letiste;
    }

    /**
     * @return the kodLetadla
     */
    public String getKodLetadla() {
        return kodLetadla;
    }

    /**
     * @param kodLetadla the kodLetadla to set
     */
    public void setKodLetadla(String kodLetadla) {
        this.kodLetadla = kodLetadla;
    }

    /**
     * @return the kapacita
     */
    public String getKapacita() {
        return kapacita;
    }

    /**
     * @param kapacita the kapacita to set
     */
    public void setKapacita(String kapacita) {
        this.kapacita = kapacita;
    }

    /**
     * @return the dolet
     */
    public Integer getDolet() {
        return dolet;
    }

    /**
     * @param dolet the dolet to set
     */
    public void setDolet(Integer dolet) {
        this.dolet = dolet;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        final Letadlo other = (Letadlo) obj;
        if (this.kodLetadla != other.kodLetadla && (this.kodLetadla == null || !this.kodLetadla.equals(other.kodLetadla))) {
            return false;
        }
        return true;
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 79 * hash + (this.kodLetadla != null ? this.kodLetadla.hashCode() : 0);
        hash = 79 * hash + (this.kapacita != null ? this.kapacita.hashCode() : 0);
        hash = 79 * hash + (this.dolet != null ? this.dolet.hashCode() : 0);
        return hash;
    }

    /**
     * @return the id
     */
    public Long getId() {
        return id;
    }

    /**
     * @param id the id to set
     */
    public void setId(Long id) {
        this.id = id;
    }

    /**
     * @return the seznamLinek
     */
    public Set<Linka> getSeznamLinek() {
        return seznamLinek;
    }

    /**
     * @param seznamLinek the seznamLinek to set
     */
    public void setSeznamLinek(Set<Linka> seznamLinek) {
        this.seznamLinek = seznamLinek;
    }

    /**
     * @return the letiste
     */
    public String getLetiste() {
        return letiste;
    }

    /**
     * @param letiste the letiste to set
     */
    public void setLetiste(String letiste) {
        this.letiste = letiste;
    }