Allocating zero capacity ByteBuffer

Question

Can anybody please tell me what are those possible purposes of allocating zero-length buffer?

ByteBuffer.allocate(0); // no IllegalArgumentException

Why the one who designed the API did this?

Thanks for comments and answers.

I hope there will be an update like this. :)

public abstract class ByteBuffer
    extends Buffer
    implements Comparable<ByteBuffer> {

    public static final ByteBuffer VOID = allocate(0);
}

Why not? If you're passed an arbitrary length, what's the point of throwing? — Louis Wasserman, Aug 14 '13 at 04:55
I think the same reason `byte[] b = new byte[0]` is allowed. If its negative only then its logically impossible. — rocketboy, Aug 14 '13 at 04:58

score 6 · Accepted Answer · answered Aug 14 '13 at 05:04

6

If you have a method that must return a ByteBuffer and returning null is inappropriate for whatever reason, but you have no data to return, then returning a zero-length ByteBuffer would satisfy those conditions.

answered Aug 14 '13 at 05:04

Jason C

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score 2 · Answer 2 · answered Aug 14 '13 at 05:14

2

This can be used to implement Null Object design pattern http://en.wikipedia.org/wiki/Null_Object_pattern, similar to Collections.emptyList and others, creates an immutable object that can be reused.

answered Aug 14 '13 at 05:14

Evgeniy Dorofeev

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Allocating zero capacity ByteBuffer

2 Answers2

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