see if varible is declared

[joelmac]

Hi there,

Is there a way that I can see if a varible is declared?

I'm including Headers on my pages using <%@include file="Header.jsp"%>. Some pages will declare varibles for the Header to read, but if no varible is declared I want the Header to just ignore it. How would I do this?

Thanks,

________________________
JoelMac

 

[jemminger]

perhaps store your variables in a HashMap, and see if the key for your variable exists? like

HashMap vars = new HashMap();

if (vars.containsKey("someKey")) {
  //  var exists
}

=========================================================
-jeff

http://www.jeffemminger.com

try { succeed(); } catch(E) { tryAgain(); } finally { rtfm(); }

 

[joelmac]

That's a good idea, but I still have to declare something. I want most of my pages to behave in a 'default' manner and only declare and pass the varible for special cases.

________________________
JoelMac

 

[jemminger]

welcome to strongly-typed languages.


=========================================================
-jeff

http://www.jeffemminger.com

try { succeed(); } catch(E) { tryAgain(); } finally { rtfm(); }

 

[joelmac]

hmmm, that's what I thought, Thanks anyway.

________________________
JoelMac

 

[joelmac]

I've found a solution to my problem. I've declared my HashMap in the Header like this:

<%!  //  <--- NOTE: the "!"
     HashMap props = new HashMap();
%>

This way I can refer to the props variable in files that include the Header before the line where the Header is included.

________________________
JoelMac