Writes a codec footer, which records both a checksum algorithm ID and a checksum. this footer can be parsed and validated with
#checkFooter(ChecksumIndexInput) checkFooter().
CodecFooter --> Magic,AlgorithmID,Checksum
- Magic --> DataOutput#writeInt Uint32. this identifies the start of the footer. It is always {@value #FOOTER_MAGIC}.
- AlgorithmID --> DataOutput#writeInt Uint32. this indicates the checksum algorithm used. Currently this is always 0, for zlib-crc32.
- Checksum --> DataOutput#writeLong Uint32. The actual checksum value for all previous bytes in the stream, including the bytes from Magic and AlgorithmID.
If there is an I/O error writing to the underlying medium.