question: private int parseHeaderNonce ( final byte [ ] b , final int off ) throws ParseException { final int len = b . length - off ; if ( len >= nonceLen_ ) { headerNonce_ = Arrays . copyOfRange ( b , off , off + nonceLen_ ) ; return nonceLen_ ; } else { throw new ParseException ( "Not enough bytes to parse header nonce" ) ; } }
target:  Parse the header nonce in the provided bytes. It looks for bytes of the size defined by the nonce length in the provided bytes starting at the specified off. <p> If successful, it returns the size of the parsed bytes which is the nonce length. On failure, it throws a parse exception.