VB man goes Java. Casting..

From: Alvin Ryder (alvin321_at_telstra.com)
Date: 05/25/04 

Date: 24 May 2004 19:31:09 -0700

Hi,

I'm a VB man gone Java, sometimes I write code like

public aMethod( Object o )
{
   String error = ""

   if o instanceof X
     ProcessX (o)

   else if o instanceof Y
     ProcessY (o)

   else if o instanceof Z {
     int mode = 2
     ProcessX (o, mode) // Similar to X but a little different
   }
   else if ... about 10 of these
     Process
   else
     error = "Error - unknown type " + o.getClass().getName()
}

But my OO-guru friend, in polite words, says this is crap.

He says do
  Base o = new X()
  o.process()

instead of
  ProcessX (o)
  ProcessY (o)

Should I explore that idea?

I am not interested in the exceptional, extreme, fance, guru, or
overly-testosterone cases I just want to know what is the *basic main
line majority of cases OO way*?

Yes I know there's another downcasting thread on this NG, but it's way
too advanced. Can we *please* keep this thread simple and acrnonym
free :-) No I'm not a moron, I'm just not familiar with these
particular concepts.

Thanks in advance
Alvin

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