HmacSHA256 によるハッシュのサンプル

HmacSha256Main.java

package nu.mine.kino;

import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;

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

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.digest.HmacUtils;

public class HmacSha256Main {

    public static void main(String[] args)
            throws InvalidKeyException, NoSuchAlgorithmException {
        String data = "Hello, world!";
        String key = "aaaaaaaaaabbbbbbaaaaaaaaaabbbbbb"; // <-256bitの共通鍵

        String result01 = Base64
                .encodeBase64URLSafeString(hmacSha256(key, data));
        String result02 = Base64
                .encodeBase64URLSafeString(HmacUtils.hmacSha256(key, data));
        System.out.println(result01);
        System.out.println(result02);

    }

    public static byte[] hmacSha256(String secretKey, String data)
            throws NoSuchAlgorithmException, InvalidKeyException {
        String algorithm = "HmacSHA256";
        SecretKey key = new SecretKeySpec(secretKey.getBytes(), algorithm);

        Mac mac = Mac.getInstance(algorithm);
        mac.init(key);
        mac.update(data.getBytes());

        return mac.doFinal();
    }

}