Hello,

I'm trying to get a simple increment generator working on a MySQL database that I'm running on my notebook computer. The generator won't instatiate. I figure I must have forgotten some params. I've looked all over this website and the reference docs for params that I might be missing; however, I don't see the increment generator described anywhere -- at least not fully.

I've also read the source code and short documentation for class package org.hibernate.id.IncrementGenerator

Could someone please point to where I should look for a complete description of the increment generator (and other generators for that matter)?

Thanks!
P.

Hibernate version:
hibernate2


Mapping documents:
>
<class
name="com.myco.product.dao.hibernate.entity.ObjTypHibernateEntity"
table="OBJTYP"
>
<id
name="ID"
column="ID"
type="java.lang.Long"
unsaved-value="null"
>
<generator class="increment"> </generator>
</id>

Full stack trace of any exception that occurs:
ehcache.hibernate.Provider
Feb 5, 2006 3:20:30 PM net.sf.hibernate.cfg.Configuration configureCaches
INFO: instantiating and configuring caches
Feb 5, 2006 3:20:30 PM net.sf.hibernate.impl.SessionFactoryImpl <init>
INFO: building session factory
About to throw ExceptionInInitializerError: net.sf.hibernate.MappingException: could not instantiate id generator
java.lang.NoClassDefFoundError
at de.kemaiev.elektra.dao.hibernate.AbstractHibernateDAO.findAll(AbstractHibernateDAO.java:130)
at de.kemaiev.elektra.dao.hibernate.ObjTypHibernateDAO.findAll(ObjTypHibernateDAO.java:31)
at de.kemaiev.elektra

Name and version of the database you are using:
MySQL 5.0

Pls try to use this format sample code
*******************************************************
<hibernate-mapping package="hibernate.loginDB">

<class name="Userlogin" table="userlogin">
<id name="id" column="ID" type="integer">
<generator class="increment"/>
</id>

<property name="password" column="PASSWORD" type="string" not-null="true" />

</class>
</hibernate-mapping>

********************************************************

Userlogin --- > Name of the mapping file
userlogin ------> Database table name
id ------> particular field of the Userlogin.java
ID ---- > db column name

does not look like a parameter problem. You are getting a java.lang.NoClassDefFoundError. So check your log files for more info. You might be missing some jar files.

Thanks for the replies. I tried to do as suggested, but it didn't work the way I'd hoped. Maybe I did something wrong...

Part of the problem is that I was using MySQL for the database and was trying to refactor from an Oracle database. The Oracle app uses sequences whereas MySQL doesn't. So I had to think of another strategy. That's why I tried using the increment generator.

Anyway, I've decided to scrap MySQL and use Personal Oracle XE for my notebook computer instead. It makes things easier all-around because I don't have to refactor.

It all comes down to money in the end. I get paid to design and develop applications, not to configure stuff. As soon as I see that something is going to cause a problem, I have to either bail out or do in on my own time. This time I chose to bail out :)

Thanks again for the help!