org.ibernate.PropertyNotFoundException:在类模型中找不到id的getter。请联系

我正在尝试学习Hibernate,并遵循本教程: http://www.visualcplusdotnet.com/javaopensource/javahibernateswingdesktopapp5.html 除了我使用自己的示例数据库。我已经为我的 contact 表,如下所示:

Netbeans自动生成了一个.java文件( Contact.java ):

package model;
// Generated Mar 6, 2015 12:04:10 AM by Hibernate Tools 4.3.1



/**
 * Contact generated by hbm2java
 */
public class Contact  implements java.io.Serializable {


     private Integer id;
     private String firstname;
     private String lastname;
     private String email;
     private String phone;
     private boolean active;

    public Contact() {
    }


    public Contact(String firstname, String lastname, boolean active) {
        this.firstname = firstname;
        this.lastname = lastname;
        this.active = active;
    }
    public Contact(String firstname, String lastname, String email, String phone, boolean active) {
       this.firstname = firstname;
       this.lastname = lastname;
       this.email = email;
       this.phone = phone;
       this.active = active;
    }

    public Integer getId() {
        return this.id;
    }

    public void setId(Integer id) {
        this.id = id;
    }
    public String getFirstname() {
        return this.firstname;
    }

    public void setFirstname(String firstname) {
        this.firstname = firstname;
    }
    public String getLastname() {
        return this.lastname;
    }

    public void setLastname(String lastname) {
        this.lastname = lastname;
    }
    public String getEmail() {
        return this.email;
    }

    public void setEmail(String email) {
        this.email = email;
    }
    public String getPhone() {
        return this.phone;
    }

    public void setPhone(String phone) {
        this.phone = phone;
    }
    public boolean isActive() {
        return this.active;
    }

    public void setActive(boolean active) {
        this.active = active;
    }




}

以及一个.xml文件(Contact.hbm.xml)

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<!-- Generated Mar 6, 2015 12:04:12 AM by Hibernate Tools 4.3.1 -->
<hibernate-mapping>
    <class name="model.Contact" table="contact" catalog="crmtool" optimistic-lock="version">
        <id name="id" type="java.lang.Integer">
            <column name="id" />
            <generator class="identity" />
        </id>
        <property name="firstname" type="string">
            <column name="firstname" length="100" not-null="true" />
        </property>
        <property name="lastname" type="string">
            <column name="lastname" length="100" not-null="true" />
        </property>
        <property name="email" type="string">
            <column name="email" length="100" />
        </property>
        <property name="phone" type="string">
            <column name="phone" length="10" />
        </property>
        <property name="active" type="boolean">
            <column name="active" not-null="true" />
        </property>
    </class>
</hibernate-mapping>

在清理和构建之后,当我运行此HQL查询时:

from Contact

我收到此错误:

org.hibernate.PropertyNotFoundException: Could not find a getter for id in class model.Contact
at org.hibernate.property.BasicPropertyAccessor.createGetter(BasicPropertyAccessor.java:310)
at org.hibernate.property.BasicPropertyAccessor.getGetter(BasicPropertyAccessor.java:304)
at org.hibernate.tuple.PropertyFactory.getGetter(PropertyFactory.java:497)
at org.hibernate.tuple.PropertyFactory.buildIdentifierAttribute(PropertyFactory.java:87)
at org.hibernate.tuple.entity.EntityMetamodel.<init>(EntityMetamodel.java:163)
at org.hibernate.persister.entity.AbstractEntityPersister.<init>(AbstractEntityPersister.java:520)
at org.hibernate.persister.entity.SingleTableEntityPersister.<init>(SingleTableEntityPersister.java:148)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:408)
at org.hibernate.persister.internal.PersisterFactoryImpl.create(PersisterFactoryImpl.java:163)
at org.hibernate.persister.internal.PersisterFactoryImpl.createEntityPersister(PersisterFactoryImpl.java:135)
at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:400)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1857)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1928)

阅读这些问题的答案后:

• Hibernate - PropertyNotFoundException: Could not find a getter for
• PropertyNotFoundException: Could not find a getter for lastMoveDate in class com.hib.objects.GameBoard
• org.hibernate.PropertyNotFoundException: could not find getter for customerId in class Address

我想答案一定是路不对 id 正在被getter大写,所以我尝试:

public Integer getid() {
    return this.id;
}

public int getId() {
    return this.id;
}

public int getid() {
    return this.id;
}

各种各样的事情,但仍然没有起作用。

有人知道我为什么收到这个错误吗?