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From: David Lamb <dalamb@cs.queensu.ca>
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Subject: Re: Class.forName().newInstance() vs new
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Date: Sat, 11 Jun 2011 13:46:42 -0400
Xref: x330-a1.tempe.blueboxinc.net comp.lang.java.programmer:5207

On 11/06/2011 1:13 PM, Abu Yahya wrote:
> My question is: Does using if-else statements like the above really
> improve performance? What is the best approach to instantiate classes
> whose type you don't know at compile time?

That code is unlikely to be in some critical inner loop, so any 
efficiency gains would be marginal. Your original solution requires no 
change if the possible classes change and is simpler to understand, each 
of which on its own wins out over marginal gains in efficiency.