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From: Jan Burse <janburse@fastmail.fm>
Newsgroups: comp.lang.java.programmer
Subject: Re: setSize ArrayList, when will it come?
Date: Wed, 10 Aug 2011 12:35:23 +0200
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.java.programmer:6967

Mayeul schrieb:
>>
>> So there are 10 temporary array allocations, until
>> we reach the final array. Also the resultinhg elementData
>> has 39 excess place holders which I don't need.
>
> Nope

Yes that you are right, since array list does override
the addAll method, and there they do set the size correctly.

But a new object pops up there. The CopiesList is materialized.
Here you see the code:

     public boolean addAll(Collection<? extends E> c) {
	Object[] a = c.toArray();
         int numNew = a.length;
	ensureCapacity(size + numNew);  // Increments modCount
         System.arraycopy(a, 0, elementData, size, numNew);
         size += numNew;
	return numNew != 0;
     }

So there are two temporary objects, the CopiesList, and the
Object[] a from above. No enumerator.

Not nice