Good Day,

I am trying to make a class extends relationship between several classes, and I have found now luck in examples to do this, this should be rather simple I would think, but don't seem to find the right thing, so here is what I am asking for.









this is the setup, and I have other Pto? classes that do the same think, so I need a little help to map these classes.

and do I need the hashcode and equals in all classes????

and put this all in one table.

thanks in advance,

I assume no one has done any complex programs, since no senior members have committed on this.

maybe I need to look at something other than hibernate.

Your assumption is wrong. There are lots of really complex programs using hibernate. You are looking for the right strategy to map your entities to table, so have a look at
@Inheritance(strategy=InheritanceType.JOINED/SINGLE_TABLE/TABLE_PER_CLASS) and @MappedSuperclass

If you need equals/hashCode depends on your application. Have a look at http://docs.jboss.org/hibernate/orm/3.3 ... asses.html (Chapter 4.3)

Well, I have tried the

@Entity
@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
@Table(name="pton")
@DiscriminatorColumn(name="TYPE", discriminatorType=DiscriminatorType.INTEGER)
public class PtoN extends Relation implements Serializable {

and

@Entity
@DiscriminatorValue("1")
public class Relation extends RtTemplate implements Serializable {

and

@Entity
@DiscriminatorValue("1")
public class RtTemplate extends Resource implements Comparable<RtTemplate>, Serializable {

and

@MappedSuperclass
public abstract class Resource implements Serializable {

but then it wants to insert a table called ReTemplate instead of using the pton as designated above.

I wish the Dtype column was not there, but I could careless for an extra column at this point.

thanks.

Solved, by my own experimentations.

this is how it is done.







and so on, this will allow for multiple Pto? classes to be mapped to the extended classes, beware of date's, that is what I used the @Transient for to deal with that particular varible.

So this works well, as least for what I am trying to accomplish.

Steve

From what I have learned, through my dealing, I have multiple clases the extend the same classes, so for instance

So what I have done is set all my extended classes as a superclass using the one class as InheritanceType.JOINED, and this is just to make my one
single table from all the classes associated with it, this is what I wanted to accomplish, so to give you a idea, ptop extends relation, extends template,
extends resource. and with that said, my other classes would be pton extends relation, extends template, extends resource and each main class listed in my solution was a single table, which is what I wanted and they all work fine, then setup you dao to presist and it works. I use the Entity on the ptop,pton, pto? for what tables I need to populate.

I hope this gives some insight, and by the way, I did this from trial and error, I did not find any documentation to help as well.

If you need more help, post the top part of the model classes and I as I did above.

Steve