ByteBufferInputStream & ByteBufferOutputStream

Question

Anyone else feel that these classes should have been part of nio? They're easy enough to implement, it's just that they seem to be obviously missing. They'd also be a nice way to tie java.nio and java.io together. I particularly noticed this when trying to use the JAXB api. When marshalling and unmarshalling objects JAXB expects a stream interface, but I've been using nio and consequently buffers.
-S

Answer 1

one way around this is to read you data into a
ByteBuffer. Call
the array() method on the buffer (this may or may not
be supported but
probably is). You can then wrap the returned array
into a
ByteArrayInputStream. The reverse can also be done.Creating the ByteArrayInputStream from the byte array backing the ByteBuffer works as long as you specify the constructor taking an offset and length to which you pass position() and remaining(). I just thought it'd be cleaner to implement a ByteBufferInputStream.
Create a ByteArrayOutputStream of an appropriate size.
write to it.
call toByteArray() to retrive the underlying array.
Call ByteBuffer.wrap(array) to wrap the byte array
into a ByteBuffer.
This last one can be done more efficiently by using
the
Channels.newChannel(OutputStream) method.
matfudOn the output side, calling toByteArray() on ByteArrayOutputStream doesn't give you access to the backing byte array but instead makes a copy. Again, ByteBufferOutputStream seems cleaner.
Thanks to both of you for the suggestions.
-S