hibernate的一个问题,请大家帮助

请大家看下为什么报错,怎样解决?
Book.java
package bean;

public class Book implements java.io.Serializable {



     private Integer bookId;
     private String bookName;
     private String bookAuthor;
     private double bookPrice;


    /** default constructor */
    public Book() {
    }

   
    /** full constructor */
    public Book(String bookName, String bookAuthor, double bookPrice) {
        this.bookName = bookName;
        this.bookAuthor = bookAuthor;
        this.bookPrice = bookPrice;
    }

  
    // Property accessors

    public Integer getBookId() {
        return this.bookId;
    }
   
    public void setBookId(Integer bookId) {
        this.bookId = bookId;
    }

    public String getBookName() {
        return this.bookName;
    }
   
    public void setBookName(String bookName) {
        this.bookName = bookName;
    }

    public String getBookAuthor() {
        return this.bookAuthor;
    }
   
    public void setBookAuthor(String bookAuthor) {
        this.bookAuthor = bookAuthor;
    }

    public double getBookPrice() {
        return this.bookPrice;
    }
   
    public void setBookPrice(double bookPrice) {
        this.bookPrice = bookPrice;
    }

}
Book.hbm.xml
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!--
    Mapping file autogenerated by MyEclipse - Hibernate Tools
-->
<hibernate-mapping>
    <class name="bean.Book" table="book" catalog="bookstoressh">
        <id name="bookId" type="integer">
            <column name="book_id" />
            <generator class="native" />
        </id>
        <property name="bookName" type="string">
            <column name="book_name" length="100" not-null="true" />
        </property>
        <property name="bookAuthor" type="string">
            <column name="book_author" length="100" not-null="true" />
        </property>
        <property name="bookPrice" type="double">
            <column name="book_price" precision="22" scale="0" not-null="true" />
        </property>
    </class>
</hibernate-mapping>

hibernate.cfg.xml
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
          "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
          "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<!-- Generated by MyEclipse Hibernate Tools.                   -->
<hibernate-configuration>

<session-factory>
<property name="myeclipse.connection.profile">
bookstoressh
</property>
<property name="connection.url">
jdbc:mysql://localhost:3306/bookstoressh
</property>
<property name="connection.username">root</property>
<property name="connection.password">123</property>
<property name="connection.driver_class">
org.gjt.mm.mysql.Driver
</property>
<property name="dialect">
org.hibernate.dialect.MySQLDialect
</property>
<property name="hibernate.transaction.factory_class">
org.hibernate.transaction.JDBCTransactionFactory
</property>
<property name="show_sql">true</property>
<property name="hbm2ddl.auto">true</property>
<mapping resource="bean/Book.hbm.xml" />

</session-factory>

</hibernate-configuration>
报错情况:
Hibernate: select book0_.book_id as book1_0_, book0_.book_name as book2_0_0_, book0_.book_author as book3_0_0_, book0_.book_price as book4_0_0_ from bookstoressh.book book0_ where book0_.book_id=?
org.hibernate.HibernateException: More than one row with the given identifier was found: 2, for class: bean.Book
at org.hibernate.loader.entity.EntityLoader.load(EntityLoader.java:137)
at org.hibernate.loader.entity.EntityLoader.load(EntityLoader.java:101)
at org.hibernate.persister.entity.BasicEntityPersister.load(BasicEntityPersister.java:2471)
at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:351)
at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:332)
at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:113)
at org.hibernate.event.def.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:167)
at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:79)
at org.hibernate.impl.SessionImpl.get(SessionImpl.java:621)
at org.hibernate.impl.SessionImpl.get(SessionImpl.java:614)
at service.Work.sec(Work.java:22)
at service.Work.main(Work.java:40)
业务类 Work.java
package service;




import org.hibernate.Session;
import org.hibernate.Transaction;

import bean.Book;
import bean.HibernateSessionFactory;



public class Work {
void sec(){

Session session = null ;
  try {

          session = HibernateSessionFactory.getCurrentSession();
          Transaction f =  session.beginTransaction();
   Book book=(Book)session.get( Book.class,new Integer(2));//引起异常的地方，？？？？      System.out.println(book.getBookName());
    
     f.commit();
   
      } catch (Exception hex) {
      hex.printStackTrace();
         } finally {
          if (session != null) {
              HibernateSessionFactory.closeCurrentSession();
             
              }
      
          }}


public static void main(String[] args) {
Work work=new Work();
    work.sec();

}
}

评论

4 楼 xuzhiwen72 2007-06-11  

javachs 写道

去数据库看看是不是有两条相同的记录.

只有一条记录 没有相同的.主键也不可能让他相同了

3 楼 javachs 2007-06-11  

去数据库看看是不是有两条相同的记录.

2 楼 xuzhiwen72 2007-06-11  

javachs 写道

没有主键,记录不唯一,你看英文报错就知道了.

但是我设置了主键,用sqlserver设置通过了.

1 楼 javachs 2007-06-11  

没有主键,记录不唯一,你看英文报错就知道了.