Can we create multiple instances of a Bean in a JSP file?

Hi,
I am new to JSP & Servlets programming.
I need to write a servlet that connects to a database via JDBC ( using IBM DB2 dbms) , sets some Beans with the tuples in the relevant table.
Then, I need to have a JSP "read" ( or "get") info from the Beans & display the contents to the client.
( At a time only 5 tuples must be visible in the UI , with Next & Prev links ...)
I am using Tomcat 4.0 for this...
Can any one please help me regarding HOW to go abt it ?
Esp., should we create 1 instance of a Bean , ( say "DataBean") for EACH tuple , or is there a way to do it with only 1 instance...
Please, guide me... ( if not possible, at least give me some hints to some GOOD resources ( books, sites,etc.), that deal with this kind of applications)
Thanks,
Raghu.

Once again, thanx a lot for your detailed help -- evnafets !!
I think I am gaining in my knowledge of JSP & Servlets thanks to your help...
Now, I am tackling the issue of selecting the BEST way of "STORING" which "PAGE" no. I am displaying.
Say, I have only 15 tuples(ROWS), & with 5 tuples displayed per page, I have to have 3 "pages", & I need to accomplish the handling of "Prev" & "Next" links using only 1 Servlet & 1 JSP ( apart from the Authorization servlet ).
I am thinking of storing a "session-scoped" variable called "page-num". Do you think it's the best way?
Or should I score it as an "application-scoped variable" ( i.e., in the ServletContext ...) ??
Also, I have got no clues as to which of the following would be a better idea :
(a) Fetch ALL the tuples in the table & set as many beans. And then display the corresponding 5 tuples in each page.
Here, more bean instances are needed to hold the data which gets repeatedly passed around ( when Prev & Next links are clicked ).
OR ..
(b)Fetch only 5 tuples at a time . I think this may be done by creating a scrollable Resultset & then moving around to the appropriate ROW by saying
resultSet.absolute( (page_num - 1)*5 + 1 ); & then fetching 5 tuples relative to this row.
In this case I will need atmost 5 Bean objects per request.
And YES, one more thing , WOULD you PLEASE try & give me some guidance towards some good references to JSP, Servlets & J2EE ? ( Links, Books, anything ! )
Sorry for the TROUBLE I gave, but THANKS a lot for the TROUBLE u took ! ;-)
Thanks & Regards,
Raghu

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Creating multiple instances

Below are two methods to create multiple instances. Clearly,
method 2 is more efficient. However, if I use method 2 I don't know
how to modify a specific instance later in my code. For example,
using method 1 I can just write:
tf1.alpha=0
but I don't know how I can target a specific instance using
method 2. Writing tf.alpha=0 will only target my last instance. How
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instance by name?

"SiHoop" <[email protected]> wrote in
message
news:gmkkn3$ok8$[email protected]..
> Below are two methods to create multiple instances.
Clearly, method 2 is
> more
> efficient. However, if I use method 2 I don't know how
to modify a
> specific
> instance later in my code. For example, using method 1 I
can just write:
> tf1.alpha=0
> but I don't know how I can target a specific instance
using method 2.
> Writing
> tf.alpha=0 will only target my last instance. How do I
put something in my
> loop
> to allow me to identify every instance by name?
>
>
>
> Method 1:
> var tf1:TextField=new TextField
> var tf2:TextField=new TextField
> var tf3:TextField=new TextField
> tf1.text=myArray[0]
> tf2.text=myArray[0]
> tf3.text=myArray[0]
> tf1.setTextFormat(format4)
> tf2.setTextFormat(format4)
> tf3.setTextFormat(format4)
>
> Method 2:
> for(var i:uint:=0;i<3;i++){
> var tf:TextField=new TextField
> tf.text=myArray
> thisi["tf"+i].setTextFormat(format4)
> }
>
var instances:Array=new Array();
for(var i:uint:=0;i<3;i++){
var tf:TextField=new TextField
tf.text=myArray
thisi["tf"+i].setTextFormat(format4)
instances.push(tf);
HTH;
Amy

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