Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.commons.codec.digest; import java.io.IOException; import java.io.InputStream; import java.security.InvalidKeyException; import java.security.Key; import java.security.NoSuchAlgorithmException; import javax.crypto.Mac; import javax.crypto.spec.SecretKeySpec; import org.apache.commons.codec.binary.Hex; import org.apache.commons.codec.binary.StringUtils; /** * Simplifies common {@link javax.crypto.Mac} tasks. This class is immutable and thread-safe. * * * <p> * <strong>Note: Not all JCE implementations supports all algorithms. If not supported, an IllegalArgumentException is * thrown.</strong> * </p> * * @since 1.10 * @version $Id: HmacUtils.java 1634411 2014-10-27 00:35:43Z ggregory $ */ public final class HmacUtils { private static final int STREAM_BUFFER_LENGTH = 1024; /** * Returns an initialized <code>Mac</code> for the HmacMD5 algorithm. * <p> * Every implementation of the Java platform is required to support this standard Mac algorithm. * </p> * * @param key * They key for the keyed digest (must not be null) * @return A Mac instance initialized with the given key. * @see Mac#getInstance(String) * @see Mac#init(Key) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static Mac getHmacMd5(final byte[] key) { return getInitializedMac(HmacAlgorithms.HMAC_MD5, key); } /** * Returns an initialized <code>Mac</code> for the HmacSHA1 algorithm. * <p> * Every implementation of the Java platform is required to support this standard Mac algorithm. * </p> * * @param key * They key for the keyed digest (must not be null) * @return A Mac instance initialized with the given key. * @see Mac#getInstance(String) * @see Mac#init(Key) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static Mac getHmacSha1(final byte[] key) { return getInitializedMac(HmacAlgorithms.HMAC_SHA_1, key); } /** * Returns an initialized <code>Mac</code> for the HmacSHA256 algorithm. * <p> * Every implementation of the Java platform is required to support this standard Mac algorithm. * </p> * * @param key * They key for the keyed digest (must not be null) * @return A Mac instance initialized with the given key. * @see Mac#getInstance(String) * @see Mac#init(Key) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static Mac getHmacSha256(final byte[] key) { return getInitializedMac(HmacAlgorithms.HMAC_SHA_256, key); } /** * Returns an initialized <code>Mac</code> for the HmacSHA384 algorithm. * <p> * Every implementation of the Java platform is <em>not</em> required to support this Mac algorithm. * </p> * * @param key * They key for the keyed digest (must not be null) * @return A Mac instance initialized with the given key. * @see Mac#getInstance(String) * @see Mac#init(Key) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static Mac getHmacSha384(final byte[] key) { return getInitializedMac(HmacAlgorithms.HMAC_SHA_384, key); } /** * Returns an initialized <code>Mac</code> for the HmacSHA512 algorithm. * <p> * Every implementation of the Java platform is <em>not</em> required to support this Mac algorithm. * </p> * * @param key * They key for the keyed digest (must not be null) * @return A Mac instance initialized with the given key. * @see Mac#getInstance(String) * @see Mac#init(Key) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static Mac getHmacSha512(final byte[] key) { return getInitializedMac(HmacAlgorithms.HMAC_SHA_512, key); } /** * Returns an initialized <code>Mac</code> for the given <code>algorithm</code>. * * @param algorithm * the name of the algorithm requested. See <a href= * "http://docs.oracle.com/javase/6/docs/technotes/guides/security/crypto/CryptoSpec.html#AppA" >Appendix * A in the Java Cryptography Architecture Reference Guide</a> for information about standard algorithm * names. * @param key * They key for the keyed digest (must not be null) * @return A Mac instance initialized with the given key. * @see Mac#getInstance(String) * @see Mac#init(Key) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static Mac getInitializedMac(final HmacAlgorithms algorithm, final byte[] key) { return getInitializedMac(algorithm.toString(), key); } /** * Returns an initialized <code>Mac</code> for the given <code>algorithm</code>. * * @param algorithm * the name of the algorithm requested. See <a href= * "http://docs.oracle.com/javase/6/docs/technotes/guides/security/crypto/CryptoSpec.html#AppA" >Appendix * A in the Java Cryptography Architecture Reference Guide</a> for information about standard algorithm * names. * @param key * They key for the keyed digest (must not be null) * @return A Mac instance initialized with the given key. * @see Mac#getInstance(String) * @see Mac#init(Key) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static Mac getInitializedMac(final String algorithm, final byte[] key) { if (key == null) { throw new IllegalArgumentException("Null key"); } try { final SecretKeySpec keySpec = new SecretKeySpec(key, algorithm); final Mac mac = Mac.getInstance(algorithm); mac.init(keySpec); return mac; } catch (final NoSuchAlgorithmException e) { throw new IllegalArgumentException(e); } catch (final InvalidKeyException e) { throw new IllegalArgumentException(e); } } // hmacMd5 /** * Returns a HmacMD5 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacMD5 MAC for the given key and value * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacMd5(final byte[] key, final byte[] valueToDigest) { try { return getHmacMd5(key).doFinal(valueToDigest); } catch (final IllegalStateException e) { // cannot happen throw new IllegalArgumentException(e); } } /** * Returns a HmacMD5 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest * <p> * The InputStream must not be null and will not be closed * </p> * @return HmacMD5 MAC for the given key and value * @throws IOException * If an I/O error occurs. * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacMd5(final byte[] key, final InputStream valueToDigest) throws IOException { return updateHmac(getHmacMd5(key), valueToDigest).doFinal(); } /** * Returns a HmacMD5 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacMD5 MAC for the given key and value * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacMd5(final String key, final String valueToDigest) { return hmacMd5(StringUtils.getBytesUtf8(key), StringUtils.getBytesUtf8(valueToDigest)); } /** * Returns a HmacMD5 Message Authentication Code (MAC) as a hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacMD5 MAC for the given key and value as a hex string (lowercase) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacMd5Hex(final byte[] key, final byte[] valueToDigest) { return Hex.encodeHexString(hmacMd5(key, valueToDigest)); } /** * Returns a HmacMD5 Message Authentication Code (MAC) as a hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest * <p> * The InputStream must not be null and will not be closed * </p> * @return HmacMD5 MAC for the given key and value as a hex string (lowercase) * @throws IOException * If an I/O error occurs. * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacMd5Hex(final byte[] key, final InputStream valueToDigest) throws IOException { return Hex.encodeHexString(hmacMd5(key, valueToDigest)); } /** * Returns a HmacMD5 Message Authentication Code (MAC) as a hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacMD5 MAC for the given key and value as a hex string (lowercase) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacMd5Hex(final String key, final String valueToDigest) { return Hex.encodeHexString(hmacMd5(key, valueToDigest)); } // hmacSha1 /** * Returns a HmacSHA1 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA1 MAC for the given key and value * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha1(final byte[] key, final byte[] valueToDigest) { try { return getHmacSha1(key).doFinal(valueToDigest); } catch (final IllegalStateException e) { // cannot happen throw new IllegalArgumentException(e); } } /** * Returns a HmacSHA1 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest * <p> * The InputStream must not be null and will not be closed * </p> * @return HmacSHA1 MAC for the given key and value * @throws IOException * If an I/O error occurs. * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha1(final byte[] key, final InputStream valueToDigest) throws IOException { return updateHmac(getHmacSha1(key), valueToDigest).doFinal(); } /** * Returns a HmacSHA1 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA1 MAC for the given key and value * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha1(final String key, final String valueToDigest) { return hmacSha1(StringUtils.getBytesUtf8(key), StringUtils.getBytesUtf8(valueToDigest)); } /** * Returns a HmacSHA1 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA1 MAC for the given key and value as hex string (lowercase) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha1Hex(final byte[] key, final byte[] valueToDigest) { return Hex.encodeHexString(hmacSha1(key, valueToDigest)); } /** * Returns a HmacSHA1 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest * <p> * The InputStream must not be null and will not be closed * </p> * @return HmacSHA1 MAC for the given key and value as hex string (lowercase) * @throws IOException * If an I/O error occurs. * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha1Hex(final byte[] key, final InputStream valueToDigest) throws IOException { return Hex.encodeHexString(hmacSha1(key, valueToDigest)); } /** * Returns a HmacSHA1 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA1 MAC for the given key and value as hex string (lowercase) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha1Hex(final String key, final String valueToDigest) { return Hex.encodeHexString(hmacSha1(key, valueToDigest)); } // hmacSha256 /** * Returns a HmacSHA256 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA256 MAC for the given key and value * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha256(final byte[] key, final byte[] valueToDigest) { try { return getHmacSha256(key).doFinal(valueToDigest); } catch (final IllegalStateException e) { // cannot happen throw new IllegalArgumentException(e); } } /** * Returns a HmacSHA256 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest * <p> * The InputStream must not be null and will not be closed * </p> * @return HmacSHA256 MAC for the given key and value * @throws IOException * If an I/O error occurs. s * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha256(final byte[] key, final InputStream valueToDigest) throws IOException { return updateHmac(getHmacSha256(key), valueToDigest).doFinal(); } /** * Returns a HmacSHA256 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA256 MAC for the given key and value * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha256(final String key, final String valueToDigest) { return hmacSha256(StringUtils.getBytesUtf8(key), StringUtils.getBytesUtf8(valueToDigest)); } /** * Returns a HmacSHA256 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA256 MAC for the given key and value as hex string (lowercase) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha256Hex(final byte[] key, final byte[] valueToDigest) { return Hex.encodeHexString(hmacSha256(key, valueToDigest)); } /** * Returns a HmacSHA256 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest * <p> * The InputStream must not be null and will not be closed * </p> * @return HmacSHA256 MAC for the given key and value as hex string (lowercase) * @throws IOException * If an I/O error occurs. * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha256Hex(final byte[] key, final InputStream valueToDigest) throws IOException { return Hex.encodeHexString(hmacSha256(key, valueToDigest)); } /** * Returns a HmacSHA256 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA256 MAC for the given key and value as hex string (lowercase) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha256Hex(final String key, final String valueToDigest) { return Hex.encodeHexString(hmacSha256(key, valueToDigest)); } // hmacSha384 /** * Returns a HmacSHA384 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA384 MAC for the given key and value * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha384(final byte[] key, final byte[] valueToDigest) { try { return getHmacSha384(key).doFinal(valueToDigest); } catch (final IllegalStateException e) { // cannot happen throw new IllegalArgumentException(e); } } /** * Returns a HmacSHA384 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest * <p> * The InputStream must not be null and will not be closed * </p> * @return HmacSHA384 MAC for the given key and value * @throws IOException * If an I/O error occurs. * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha384(final byte[] key, final InputStream valueToDigest) throws IOException { return updateHmac(getHmacSha384(key), valueToDigest).doFinal(); } /** * Returns a HmacSHA384 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA384 MAC for the given key and value * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha384(final String key, final String valueToDigest) { return hmacSha384(StringUtils.getBytesUtf8(key), StringUtils.getBytesUtf8(valueToDigest)); } /** * Returns a HmacSHA384 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA384 MAC for the given key and value as hex string (lowercase) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha384Hex(final byte[] key, final byte[] valueToDigest) { return Hex.encodeHexString(hmacSha384(key, valueToDigest)); } /** * Returns a HmacSHA384 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest * <p> * The InputStream must not be null and will not be closed * </p> * @return HmacSHA384 MAC for the given key and value as hex string (lowercase) * @throws IOException * If an I/O error occurs. * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha384Hex(final byte[] key, final InputStream valueToDigest) throws IOException { return Hex.encodeHexString(hmacSha384(key, valueToDigest)); } /** * Returns a HmacSHA384 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA384 MAC for the given key and value as hex string (lowercase) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha384Hex(final String key, final String valueToDigest) { return Hex.encodeHexString(hmacSha384(key, valueToDigest)); } // hmacSha512 /** * Returns a HmacSHA512 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA512 MAC for the given key and value * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha512(final byte[] key, final byte[] valueToDigest) { try { return getHmacSha512(key).doFinal(valueToDigest); } catch (final IllegalStateException e) { // cannot happen throw new IllegalArgumentException(e); } } /** * Returns a HmacSHA512 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest * <p> * The InputStream must not be null and will not be closed * </p> * @return HmacSHA512 MAC for the given key and value * @throws IOException * If an I/O error occurs. * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha512(final byte[] key, final InputStream valueToDigest) throws IOException { return updateHmac(getHmacSha512(key), valueToDigest).doFinal(); } /** * Returns a HmacSHA512 Message Authentication Code (MAC) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA512 MAC for the given key and value * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static byte[] hmacSha512(final String key, final String valueToDigest) { return hmacSha512(StringUtils.getBytesUtf8(key), StringUtils.getBytesUtf8(valueToDigest)); } /** * Returns a HmacSHA512 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA512 MAC for the given key and value as hex string (lowercase) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha512Hex(final byte[] key, final byte[] valueToDigest) { return Hex.encodeHexString(hmacSha512(key, valueToDigest)); } /** * Returns a HmacSHA512 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest * <p> * The InputStream must not be null and will not be closed * </p> * @return HmacSHA512 MAC for the given key and value as hex string (lowercase) * @throws IOException * If an I/O error occurs. * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha512Hex(final byte[] key, final InputStream valueToDigest) throws IOException { return Hex.encodeHexString(hmacSha512(key, valueToDigest)); } /** * Returns a HmacSHA512 Message Authentication Code (MAC) as hex string (lowercase) for the given key and value. * * @param key * They key for the keyed digest (must not be null) * @param valueToDigest * The value (data) which should to digest (maybe empty or null) * @return HmacSHA512 MAC for the given key and value as hex string (lowercase) * @throws IllegalArgumentException * when a {@link NoSuchAlgorithmException} is caught or key is null or key is invalid. */ public static String hmacSha512Hex(final String key, final String valueToDigest) { return Hex.encodeHexString(hmacSha512(key, valueToDigest)); } // update /** * Updates the given {@link Mac}. This generates a digest for valueToDigest and the key the Mac was initialized * * @param mac * the initialized {@link Mac} to update * @param valueToDigest * the value to update the {@link Mac} with (maybe null or empty) * @return the updated {@link Mac} * @throws IllegalStateException * if the Mac was not initialized * @since 1.x */ public static Mac updateHmac(final Mac mac, final byte[] valueToDigest) { mac.reset(); mac.update(valueToDigest); return mac; } /** * Updates the given {@link Mac}. This generates a digest for valueToDigest and the key the Mac was initialized * * @param mac * the initialized {@link Mac} to update * @param valueToDigest * the value to update the {@link Mac} with * <p> * The InputStream must not be null and will not be closed * </p> * @return the updated {@link Mac} * @throws IOException * If an I/O error occurs. * @throws IllegalStateException * If the Mac was not initialized * @since 1.x */ public static Mac updateHmac(final Mac mac, final InputStream valueToDigest) throws IOException { mac.reset(); final byte[] buffer = new byte[STREAM_BUFFER_LENGTH]; int read = valueToDigest.read(buffer, 0, STREAM_BUFFER_LENGTH); while (read > -1) { mac.update(buffer, 0, read); read = valueToDigest.read(buffer, 0, STREAM_BUFFER_LENGTH); } return mac; } /** * Updates the given {@link Mac}. This generates a digest for valueToDigest and the key the Mac was initialized * * @param mac * the initialized {@link Mac} to update * @param valueToDigest * the value to update the {@link Mac} with (maybe null or empty) * @return the updated {@link Mac} * @throws IllegalStateException * if the Mac was not initialized * @since 1.x */ public static Mac updateHmac(final Mac mac, final String valueToDigest) { mac.reset(); mac.update(StringUtils.getBytesUtf8(valueToDigest)); return mac; } }