hmac.java

import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SignatureException;
import java.util.Formatter;
import java.io.BufferedReader;
import java.nio.charset.Charset;
import java.io.FileReader;
import java.math.BigInteger;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;


public class t {

      private static String toHexString(byte[] bytes) {
              Formatter formatter = new Formatter();

              for (byte b : bytes) {
                      formatter.format("%02x", b);
              }

              return formatter.toString();
      }

      public static String encode(String data, String key) throws Exception {
              final Charset asciiCs = Charset.forName("UTF-8");
              final Mac sha256_HMAC = Mac.getInstance("HmacSHA256");
              final SecretKeySpec secret_key = new javax.crypto.spec.SecretKeySpec(asciiCs.encode(key).array(), "HmacSHA256");
              sha256_HMAC.init(secret_key);
              final byte[] mac_data = sha256_HMAC.doFinal(asciiCs.encode(data).array());
              String result = "";
              for (final byte element : mac_data)
              {
                      result += Integer.toString((element & 0xff) + 0x100, 16).substring(1);
              }
              System.out.println("Result:[" + result + "]");
              return result;

      }

      public static void main(String[] args) throws Exception {
              BufferedReader br = new BufferedReader(new FileReader("1.txt"));
              try {
                      StringBuilder sb = new StringBuilder();
                      String line = br.readLine();

                      while (line != null) {
                              sb.append(line);
                              sb.append(System.lineSeparator());
                              line = br.readLine();
                      }
                      String everything = sb.toString();
                      String hmac = encode(everything, "111111");

                      System.out.println(hmac);
              } finally {
                      br.close();
              }

      }
}