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Java

Hashing Passwords

Here is some code that you can use to hash passwords or other secrets in Java. I usually prefer to have such methods in a separate utility class:

protected static MessageDigest getDigest() throws NoSuchAlgorithmException {
	if (digest == null) {
		digest = MessageDigest.getInstance(&qout;MD5&qout;);
	}
	return digest;
}
 
public static byte[] digestString(String s) {
	if (s == null) return null;
	try {
		MessageDigest digest = getDigest();
		digest.update(s.getBytes());
		return digest.digest();
	} catch (Exception e) {
		log.error(&qout;Digesting problem:&qout;, e);
	}
	return null;
}
 
public static String encodePassword(String s) {
	byte b[] = digestString(s);
	if (b == null) return null;
	String rc = new String(Base64.encodeBase64(b));
	if (rc.length() > 50) rc = rc.substring(0, 50);
	return rc;
}

Use the function encodePassword() to hash your string. Please note that the hash value is limited to a length of 50 characters.

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