Allocating zero capacity ByteBuffer [closed]

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Closed 6 years ago.

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);
}

回答1:

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.

回答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.

来源：https://stackoverflow.com/questions/18223481/allocating-zero-capacity-bytebuffer