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From: Eric Sosman <esosman@comcast-dot-net.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: convert byte array to hex string using BigInteger
Date: Thu, 20 Jun 2013 09:03:38 -0400
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On 6/20/2013 8:03 AM, Laura Schmidt wrote:
> Hi,
>
> I try to convert a byte array to a hex string like this:
>
>   private static String hex_encode (byte [] val)
>   {
>    BigInteger b = new BigInteger(val);
>
>    String t = b.toString(16);
>
>    return (t);
>   }
>
> For a long byte array it returns a "negative" hex string, i. e. starting
> with a "-" sign.
>
> But I want just the bytes in the array converted to hex representation,
> each one ranging from "00" to "FF". There should be no minus sign then.
>
> Can you help?

	// Untested:
	private static String hexEncode(byte[] val) {
	    StringBuilder buff = new StringBuilder(2 * val.length);
	    for (byte b : val) {
	        buff.append("0123456789ABCDEF".charAt((b >> 4) & 0xF));
	        buff.append("0123456789ABCDEF".charAt(b & 0xF));
	    }
	    return buff.toString();
	}

There are other ways, too.

-- 
Eric Sosman
esosman@comcast-dot-net.invalid