The fact is that color is not a string, it is a reference variable to a
String object. The value returned by request.getParameter("color") is an
address to a memory allocation where a String object resides. Inside this
object is the string "red". So if you use == to compare the reference
variable color with the string "red" you will never get a true.

Hope this helps

Fran

> -----Mensaje original-----
> De:   "Vill�n Pizarro, Julia" [SMTP:[EMAIL PROTECTED]]
> Enviado el:   viernes 19 de abril de 2002 8:50
> Para: [EMAIL PROTECTED]
> Asunto:       Re: Question about  page parameters type. String?
> 
> This answers are very helpfull and my problem is solved, but not my
> curiosity. 
> As you can see I'm not a Java expert but I don't understand why do I have
> to use this methods when color is a String.
> Just curiosity, 
> thanks,
> Julia
> 
> 
> -----Mensaje original-----
> De: Vikramjit Singh [mailto:[EMAIL PROTECTED]]
> Enviado el: viernes, 19 de abril de 2002 5:54
> Para: [EMAIL PROTECTED]
> Asunto: Re: Question about page parameters type. String?
> 
> 
> or a much faster way is like this
> 
> <%
> String color;
> color=request.getParameter("color")
> 
> if (color.intern() =="red") {
> --------------------------
>         whatever1
> }
> else {whatever2}
> 
> %>
> 
> using intern() is quite fast since in equals() each character is checked
> which is quite time consuming which intern() gives you the canonical
> representation of the string.
> in your applications try to use intern() rather than equals().
> 
> Regards,
> Vikramjit Singh,
> Systems Engineer,
> GTL Ltd.
> Ph. 7612929-1031
> 
> 
> -----Original Message-----
> From: Kesav, Ramesh [mailto:[EMAIL PROTECTED]]
> Sent: Thursday, April 18, 2002 5:19 AM
> To: [EMAIL PROTECTED]
> Subject: Re: Question about page parameters type. String?
> 
> 
> Hi bhusan,
> 
>  That's one point  but she is trying to compare using == method which is
> for
> object referecne but not the value.
> 
> 
> No need of casting as paramater always comes as a String and your color
> variable in the code is also a String so no need of casting.
> -----Original Message-----
> From:   "Vill�n Pizarro, Julia" [mailto:[EMAIL PROTECTED]]
> <mailto:[mailto:[EMAIL PROTECTED]]> 
> Sent:   Thursday, April 18, 2002 5:22 PM
> To:     [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> 
> Subject:        Question about page parameters type. String?
> 
> 
> Hi all!
> I call my_page.jsp this way
> http://my_server/my_page.jsp?color=red
> <http://my_server/my_page.jsp?color=red> 
> 
> Then I retrieve the value of the parameter "color" and then try to match
> it,
> in the following way:
> 
> <%
> String color;
> color=request.getParameter("color")
> if (color=="red") {
>         whatever1
> }
> else {whatever2}
> 
> %>
> 
> The answer is whatever2. I made sure the page is getting the parameter
> right
> by writing it out. The question is if I have to do any kind of casting.
> Thaks in advance,
> Julia
> 
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