private void readFromBuffer(ByteBuffer buf) throws IOException {
this.buf = buf;
buf.order(ByteOrder.LITTLE_ENDIAN);
header = new Header();
header.read(buf);
fixupHeader();
}
public void write(FileOutputStream fos) throws IOException {
FileChannel chan = fos.getChannel();
// Create ByteBuffer for header in case the start of our
// ByteBuffer isn't actually memory-mapped
ByteBuffer hdr = ByteBuffer.allocate(Header.writtenSize());
hdr.order(ByteOrder.LITTLE_ENDIAN);
header.write(hdr);
hdr.rewind();
chan.write(hdr);
buf.position(Header.writtenSize());
chan.write(buf);
chan.force(true);
chan.close();
}