Apr 15

How to convert a hex string to a byte array?

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The BigDecimal class makes this really easy as it has a method toByteArray() that returns exactly what we need. Just need to create a BigDecimal and call the method.

   byte[] bytes = new BigInteger(hexString, 16).toByteArray();

written by objects \\ tags: , ,


2 Responses to “How to convert a hex string to a byte array?”

  1. 1. Chien Says:
    May 20th, 2009 at 3:50 am

    Hi objects,

    Not sure if I could seek advice here…I’ve tried this code and it works :) However, the byte array generated is not the same as the original byte. I mean I used

    key = KeyGenerator.getInstance(“DES”).generateKey();
    byte[] mybytekey = key.getEncoded();

    I’ve got random key(Secret key type) and byte array. At later stage, triggered by some action, I will need to use ‘mybytekey’ to generate the ‘key’ for decryption purpose. At this stage, I am stuck when i store a hexString and try to get it back via byte[] bytes = new BigInteger(hexString, 16).toByteArray();
    the byte array values is different…

    any ideas how i should fix this? Thanks in advance.

  2. 2. objects Says:
    May 22nd, 2009 at 12:19 am

    Chien,

    Where are you getting the hexString from?

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