Hibernate session.save（）にクエリのメンバーがありません

Question

Hiii guys MAMPをDBとして使用してタスクを追加する単純なToDoList（これは私のプロジェクトのちょうど始まりです）です。 私の問題は、season.save（）がクエリの主キー（ "id"）を紛失していることです。 私は次のコードを持っている：私はこの単純なプログラムを実行しようとしていると私はのように見える例外を取得しています

package Model; 

import java.util.Date; 

public class items { 

    private int id;// primary key that connect to the users 
    private String taskname; 
    private String date; 
    private String note; 


    public items(){ 
     taskname = "basketball"; 
     note = "a fun game"; 
     date = "15/10/2016"; 
     id = 2012; 
    } 

    public items(int id, String taskName, String taskDate, String note) { 
     super(); 
     this.taskname = taskName; 
     this.date = taskDate; 
     this.note = note; 
     this.id = id; 
    } 

    public String getTaskname() { 
     return taskname; 
    } 

    public void setTaskname(String taskname) { 
     this.taskname = taskname; 
    } 

    public String getDate() { 
     return date; 
    } 

    public void setDate(String date) { 
     this.date = date; 
    } 

    public String getNote() { 
     return note; 
    } 

    public void setNote(String note) { 
     this.note = note; 
    } 

    public int getId() { 
     return id; 
    } 

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

} 

：

メインクラス：

package Model; 


    import java.util.Date; 
    import java.util.List; 

    import org.hibernate.HibernateException; 
    import org.hibernate.Session; 
    import org.hibernate.SessionFactory; 
    import org.hibernate.cfg.AnnotationConfiguration; 


    //create exception instead of HibernateException ToDoListDAOException 
    public class HibernateToDoListDAO implements IToDoListDAO { 

     SessionFactory factory = null; 
     private static final HibernateToDoListDAO _instanceDAO = new HibernateToDoListDAO(); 


     // no need to do connection or use driver to my sql 
     private HibernateToDoListDAO(){ 
      factory = new AnnotationConfiguration().configure().buildSessionFactory(); 
     } 

     public static HibernateToDoListDAO getInstance() 
     { 
      return _instanceDAO; 
     } 

     @Override 
     public void addMemorandums(items memorandum) throws HibernateException { 
      Session session = factory.openSession(); 
      try{ 
       session.beginTransaction(); 
       //create the query for memorandum members 
       session.saveOrUpdate(memorandum); 
       System.out.println("after save : user id's = "+memorandum.getId()); 

       session.getTransaction().commit(); 
      }catch(HibernateException e) 
      { 
       e.printStackTrace(); 
       if (session.getTransaction() != null) 
        session.getTransaction().rollback(); 
      }finally{ 
       session.close(); 
      } 
     } 

     @Override 
     public void updateMemorandums(items memorandum) throws HibernateException { 
      Session session = null; 
      try{ 
       session = factory.openSession(); 
       session.beginTransaction(); 
       session.update(memorandum); 
       session.getTransaction().commit(); 
      }catch(HibernateException e) 
      { 
       e.printStackTrace(); 
       if (session.getTransaction() != null) 
        session.getTransaction().rollback(); 
      }finally{ 
       session.close(); 
      } 
     } 

     @Override 
     public void deleteMemorandums(items memorandum) throws HibernateException { 
      Session session = null; 
      try{ 
       session = factory.openSession(); 
       session.beginTransaction(); 
       session.delete(memorandum); 
       session.getTransaction().commit(); 
      }catch(HibernateException e) 
      { 
       e.printStackTrace(); 
       if (session.getTransaction() != null) 
        session.getTransaction().rollback(); 
      }finally{ 
       session.close(); 
      } 
     } 

     @SuppressWarnings("unchecked") 
     @Override 
     public List<items> getMemorandums() throws HibernateException { 
      List<items> memorandum = null; 
      Session session = null; 
      try{ 
       session = factory.openSession(); 
       session.beginTransaction(); 
       memorandum = session.createQuery("from todolists").list(); 
      }catch(HibernateException e) 
      { 
       e.printStackTrace(); 
       if (session.getTransaction() != null) 
        session.getTransaction().rollback(); 
      }finally{ 
       session.close(); 
      } 
      return memorandum; 
     } 

     public static void main(String[] args) { 

      @SuppressWarnings("deprecation") 
      String dateTask = "26/11/2016"; 
      items task1 = new items(2012,"football", dateTask , "ball"); 
      HibernateToDoListDAO.getInstance().addMemorandums(task1); 

     } 
    } 

アイテム・クラスを

（例外）

Hibernate: insert into items (taskname, date, note) values (?, ?, ?) 
org.hibernate.HibernateException: The database returned no natively generated identity value 
    at org.hibernate.id.IdentifierGeneratorHelper.getGeneratedIdentity(IdentifierGeneratorHelper.java:84) 
    at org.hibernate.id.IdentityGenerator$GetGeneratedKeysDelegate.executeAndExtract(IdentityGenerator.java:98) 
    at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:57) 
    at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2329) 
    at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2836) 
    at org.hibernate.action.EntityIdentityInsertAction.execute(EntityIdentityInsertAction.java:71) 
    at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:267) 
    at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:321) 
    at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:204) 
    at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:130) 
    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:677) 
    at org.hibernate.impl.SessionImpl.saveOrUpdate(SessionImpl.java:669) 
    at org.hibernate.impl.SessionImpl.saveOrUpdate(SessionImpl.java:665) 
    at Model.HibernateToDoListDAO.addMemorandums(HibernateToDoListDAO.java:36) 
    at Model.HibernateToDoListDAO.main(HibernateToDoListDAO.java:111) 

hibernate.cfg.xmlの：

<?xml version="1.0" encoding="utf-8"?> 
<!DOCTYPE hibernate-configuration SYSTEM 
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"> 

<hibernate-configuration> 
    <session-factory> 
    <property name="hibernate.dialect"> 
     org.hibernate.dialect.MySQLDialect 
    </property> 
    <property name="hibernate.connection.driver_class"> 
     com.mysql.jdbc.Driver 
    </property> 

    <!-- Assume test is the database name --> 
    <property name="hibernate.connection.url"> 
     jdbc:mysql://localhost:3306/hit 
    </property> 
<property name="hibernate.connection.username">hit</property> 
<property name="hibernate.connection.password">hit</property> 
<property name="show_sql">true</property> 

<!-- Mapping files --> 
<mapping resource="hibernate.mapping.xml"/> 

</session-factory> 
</hibernate-configuration> 

hibernate.mapping.xml：

<?xml version="1.0" encoding="utf-8"?> 
<!DOCTYPE hibernate-mapping PUBLIC 
"-//Hibernate/Hibernate Mapping DTD//EN" 
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> 

<hibernate-mapping> 

    <!-- *********** items table ******* --> 
<!-- full class name including the packege name --> 
    <class name="Model.items" table="items"> 
     <meta attribute="class-description"> 
     This class contains the the items details. 
     </meta> 
     <id name="id" type="int" column="id"> <!-- primary key --> 
     <generator class="native"/> 
     </id> 

     <property name="taskname" column="taskname" type="string"/> 
     <property name="date" column="date" type="string"/> 
     <property name="note" column="note" type="string"/> 
    </class> 

    <!-- *********** users table ******* --> 

    <!-- full class name including the packege name --> 

    <class name="Model.users" table="users"> 
     <meta attribute="class-description"> 
     This class contains the users details. 
     </meta> 
     <id name="id" type="int" column="id"> 
     <generator class="native"/> 
     </id> 
     <property name="name" column="name" type="string"/> 
     <property name="age" column="age" type="int"/> 
    </class> 


</hibernate-mapping> 

私は（MySQLで働いて）私のDBとしてMAMPを使用しています。 問題は、クエリーが4つの変数の代わりに3つだけを挿入することです（ "id"メンバーがありません）。 誰かがこの問題の解決に手伝ってもらえますか？

ありがとうございます。

Answer 1

このエラーを回避するには、テーブルのID列を自動増分する必要があります。 ID列を自動インクリメントにするためにalter table問合せを作成します。これはあなたの問題を解決するはずです