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Re: Recommended way to make shallow copy of array

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From	v_borchert@despammed.com (Volker Borchert)
Newsgroups	comp.lang.java.programmer
Subject	Re: Recommended way to make shallow copy of array
Date	19 Jan 2015 20:15:22 GMT
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Sebastian wrote:

> - use System.arraycopy (useful in particular when copying parts of an 
> array)

That's what Array.copyOf() and Arrays.copyOfRange() do.

> The for-loop, copyOf and System.arraycopy styles clearly have 
> independent storage, a clone of a one-dimensional array has independent 
> storage, but the clone of a multi-dimensional array does not.
> 
> System.arraycopy seems to have slightly better performance. 
> Arrays.copyOf is easiest to use with dynamic typing.

The question is, what happens when the JIT kicks in and starts
inlining and/or intrinsifying...

> Differences between the various methods are small, however, and might be 
> regarded a micro-optimization.

OK that should do, at least for now and until proven wrong.

Thanks


-- 

"I'm a doctor, not a mechanic." Dr Leonard McCoy <mccoy@ncc1701.starfleet.fed>
"I'm a mechanic, not a doctor." Volker Borchert  <v_borchert@despammed.com>

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Recommended way to make shallow copy of array v_borchert@despammed.com (Volker Borchert) - 2015-01-13 19:50 +0000
  Re: Recommended way to make shallow copy of array Joerg Meier <joergmmeier@arcor.de> - 2015-01-13 22:40 +0100
    Re: Recommended way to make shallow copy of array Joerg Meier <joergmmeier@arcor.de> - 2015-01-13 22:44 +0100
  Re: Recommended way to make shallow copy of array Sebastian <news@seyweiler.dyndns.org> - 2015-01-13 23:04 +0100
    Re: Recommended way to make shallow copy of array Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-01-13 18:00 -0500
    Re: Recommended way to make shallow copy of array v_borchert@despammed.com (Volker Borchert) - 2015-01-19 20:15 +0000

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