Hi buddies!

I have a web application and I have used those frameworks:
Spring
Hibernate
Struts

Until now I had no relationships between tables but I would like to add a Many-To-One relationship in my web application. I'm using annotations and I have found some examples where I could see how implement it and I think that is well implemented.

I have a Category table whose fields are:
Id (Integer)
Name (String)

I have a GreenPoint table whose fields are:
Id (Integer)
City (String)
Location (String)
Adress (String)
etc.

I have a GreenPointHasCategory table (linked table) whose fields are:
id (Integer)
greenpoint_id (it is a FK to GreenPoint id table)
category_id (it is a FK to Category id table)


The question is the following: I have a form where an user can do a search by city or location but I also would like to do a search by category.

I know how I should do it in MySQL:

SELECT DISTINCT p.* FROM greenpoint as p, category as c, greenpoint_has_category as pc WHERE p.id = pc.greenpoint_id AND c.id = pc.category_id AND c.id = 4;
In this case the category selected is the number 4.

But I don't know how can do an SQL sentence from GreenPointDaoHibernate and in this class call to Category and GreenPointHasCategory tables.

I don't know if I have explained me.

Any advice?

Thanks in advance!

If you need some code, just tell me! ;)

-Samuel-
PS: Sorry for my english!