Sha 256 is an encryption method/algorithm. The normal text is been encrypted and stored in a hash value.

http://stackoverflow.com/questions/3103652/hash-string-via-sha-256-in-java

http://stackoverflow.com/questions/9655181/how-to-convert-a-byte-array-to-a-hex-string-in-java

http://www.sha1-online.com/sha256-java/

Here's some researching sources that I found useful. 

public static void main(String[] args) throws NoSuchAlgorithmException{
        MessageDigest md = MessageDigest.getInstance("SHA-256");
        String str = "john@doe.com";
        md.update(str.getBytes());
        byte[] digest = md.digest();
        String check = bytesToHex(digest);
        System.out.println(check);
    }
    final protected static char[] hexArray = "0123456789ABCDEF".toCharArray();
    public static String bytesToHex(byte[] bytes) {
        char[] hexChars = new char[bytes.length * 2];
        for ( int j = 0; j < bytes.length; j++ ) {
            int v = bytes[j] & 0xFF;
            hexChars[j * 2] = hexArray[v >>> 4];
            hexChars[j * 2 + 1] = hexArray[v & 0x0F];
        }
        return new String(hexChars);
    }

This is the code that I end up combining all the sources, not sure if this is the most efficient way, but this works for me.