// should bail
byte b1 = headerStream.readByte();
if (b1 == LUCENE_CODEC_HEADER_BYTE) {
// Read 3 more bytes, meaning a whole integer has been read
byte b2 = headerStream.readByte();
byte b3 = headerStream.readByte();
byte b4 = headerStream.readByte();
// Convert the 4 bytes that were read into an integer
int header = ((b1 & 0xFF) << 24) + ((b2 & 0xFF) << 16) + ((b3 & 0xFF) << 8) + ((b4 & 0xFF) << 0);
// We confirm CodecUtil's CODEC_MAGIC number (0x3FD76C17)
// ourselves here, because it allows us to read the first