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stringshellhbasejruby

How to convert string of hex digits to string wtih hexdecimal byte escapes in hbase shell (JRuby)

I have JRuby (actually Apache HBase shell). I have lot of strings which represent bytes, every character is hex digit, 2 chars per byte. Something like:

id = "faed31"

But I need string of escaped characters:

=> "\xfa\xed1"

Any solution? Failed to google and have only very general impression about Ruby.

Solution

  • Here is the code which actually solves all my tasks including output that was wanted:

    # Convert binary string to hex digits.
def bin_to_hex(s)
  s.each_byte.map { |b| b.to_s(16).rjust(2, '0') }.join
end

# Convers hex string to binary string.
def hex_to_bin(s)
  s.scan(/../).map { |x| x.hex.chr }.join
end

# HBase special 'convert and print' routine to get hex digits, process them and print.
def print_hex_to_bin(s)
  Kernel.print "\"" + Bytes.toStringBinary(s.scan(/../).map { |x| x.hex.chr }.join.to_java_bytes) + "\"\n"
end

    Composed mostly based on http://anthonylewis.com/2011/02/09/to-hex-and-back-with-ruby/