Hibernate runtime persist ?

[mark]

Let's say I have one object
class Cat{
private String name;
private int year;
}
and another

class Dog{
private BigDecimal cost;
}
and one time i sent Cat object as param to some persist function, and the
other time it is Dog, and i want to save it in the same table ? how can i do
that ?




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[Donkey Hottie]

15.10.2009 10:37, mark kirjoitti:

Let's say I have one object
class Cat{
private String name;
private int year;
}
and another

class Dog{
private BigDecimal cost;
}
and one time i sent Cat object as param to some persist function, and the
other time it is Dog, and i want to save it in the same table ? how can i do
that ?

Those would be your value objects for business logic. You would need a
separate entity bean like

class Pet
{
private String kind ; // "DOG", "CAT"
private String name ; // null for Dogs; somehow dogs do not need a name
private int year ; // 0 for Dogs; dogs do not have a year.
private BigDecimal cost ; // null for Cats, cats are free.
}

 

[mark]

Thanks for the quick reply, but i don't know how many object(Animal) i'm
going to have... and I want to do it with final number of tables to save
this properties ? I saw in hibernate that there is something calles @any
annotation.. can i use this in my problem ?

15.10.2009 10:37, mark kirjoitti:

Those would be your value objects for business logic. You would need a
separate entity bean like

class Pet
{
private String kind ; // "DOG", "CAT"
private String name ; // null for Dogs; somehow dogs do not need a
name
private int year ; // 0 for Dogs; dogs do not have a year.
private BigDecimal cost ; // null for Cats, cats are free.
}


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signature database 4482 (20091005) __________

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http://www.eset.com

 

[Donkey Hottie]

15.10.2009 11:15, mark kirjoitti:

Thanks for the quick reply, but i don't know how many object(Animal) i'm
going to have... and I want to do it with final number of tables to save
this properties ? I saw in hibernate that there is something calles @any
annotation.. can i use this in my problem ?

Sorry.. I do not know Hibernate, I try to stick with JPA only.

But you could make a table like

CREATE TABLE animal
(
java_class VARCHAR(500) ;
object CLOB ;
) ;

and serialize the Java object into the CLOB (or BLOB). One entity bean
would serve all your needs, but...

 

[Marcin Rze¼nicki]

15.10.2009 11:15, mark kirjoitti:


Sorry.. I do not know Hibernate, I try to stick with JPA only.

Hibernate is JPA compatible

But you could make a table like

CREATE TABLE animal
(
        java_class      VARCHAR(500) ;
        object          CLOB ;
) ;

and serialize the Java object into the CLOB (or BLOB). One entity bean
would serve all your needs, but...

Never do this !!!

 

[Marcin Rze¼nicki]

Let's say I have one object
class Cat{
private String name;
private int year;}

and another

class Dog{
private BigDecimal cost;}

and one time i sent Cat object as param to some persist function, and the
other time it is Dog, and i want to save it in the same table ? how can i do
that ?

You need to map inheritance onto db table. I suppose that what you
need is discriminator-based inheritance. Take a look:
http://docs.jboss.org/hibernate/sta...ml#inheritance-tablepersubclass-discriminator