text: public static long checkFooter(ChecksumIndexInput in) throws IOException {validateFooter(in);long actualChecksum = in.getChecksum();long expectedChecksum = readCRC(in);if (expectedChecksum != actualChecksum) {throw new CorruptIndexException("checksum failed (hardware problem?) : expected=" + Long.toHexString(expectedChecksum) +" actual=" + Long.toHexString(actualChecksum), in);}return actualChecksum;}