@Override
        public ByteBuffer getByteBuffer() {
            Objects.requireNonNull(byteBuffer, "Already released");
            return byteBuffer;
        }
@return The underlying {@link ByteBuffer} that was obtained from the pool.
Depending on the implementation of the pool this method may block if the pool has no buffers when called.
The returned {@link ByteBuffer} must not be used once release/close are called.
stroom-bytebuffer/src/main/java/stroom/bytebuffer/impl6/ByteBufferPoolImpl7.java