How do java classes handle searches?

how do java classes store information? and how do I get it out again?
I am a relational programmer who has decided 2 take a detour in object oriented lands.
In a relational table you store info and u get the information out through a (my)SQL query
now how does a class Project with instance project 1,2,3,.........
get the information from a project with a certain name?
eg:
projectid: 1
responsible: 1234 (<--userid)
projectname: testproject
projectid: 2
responsible: 1256
projectname: leukproject
projectid: 3
responsible: 1483
projectname: testproject
projectid: 4
responsible: 3245
projectname: darnedproject
and so on....
so lets say our class Project has a thousend instances. I want to search by name, how do i write the onces to the screen who have name "testproject"?
So how do i do this without sqlquerys, totally oop?
any help would be very much appreciated! :?

Hi NiQuil,
Let me tell you a few basic things. First, RDBMS and OOP are quite different things.
In RDBMS, you ask ur database, "hey, I want this piece of info. Get me that". But you
don't tell it how to go and search for it, right. Well, things are not as simple as that in
OOP. Here you have to specify how to get your data also. But Java will surely help you
to make it easier.
First of all, you should not map between tables (of RDBMS) and classes (of OOP),
although certainly you can do this in some crude ways. What you have to do is, put all
your projects in a single instance, and then using a method, query that instance. There
are numerous ways for querying. Several classes like Hashtable, Vector, Collection
etc etc helps you to store, search and retrieve data. But I dont think it is necessary or
helpful to describe these in detail here.
However, I would like to tell you one important point. OOP is not just about data storage
and retrieval. OOP is a way of thinking. It allows you to combine your data and operations
on it. An object is just a combination of data and operations on that data. Other objects
access this data only through an interface defined by these operations. Once you
understand this concept, life will be easier. But it takes some time, especially because
you come from RDBMS, a world which talks just about data.

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