2 * ============LICENSE_START=======================================================
4 * ================================================================================
5 * Copyright © 2017-2018 AT&T Intellectual Property. All rights reserved.
6 * Copyright © 2017-2018 Amdocs
7 * ================================================================================
8 * Licensed under the Apache License, Version 2.0 (the "License");
9 * you may not use this file except in compliance with the License.
10 * You may obtain a copy of the License at
12 * http://www.apache.org/licenses/LICENSE-2.0
14 * Unless required by applicable law or agreed to in writing, software
15 * distributed under the License is distributed on an "AS IS" BASIS,
16 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17 * See the License for the specific language governing permissions and
18 * limitations under the License.
19 * ============LICENSE_END=========================================================
21 package org.onap.crud.util;
23 import java.io.ByteArrayOutputStream;
24 import java.io.IOException;
25 import java.io.ObjectOutput;
26 import java.io.ObjectOutputStream;
27 import java.security.MessageDigest;
28 import java.security.NoSuchAlgorithmException;
31 * Generates a sha 256 hash
33 public class HashGenerator {
35 private MessageDigest messageDigest;
37 public HashGenerator() throws NoSuchAlgorithmException {
38 this.messageDigest = MessageDigest.getInstance("SHA-256");
42 * Generates a SHA 256 hash as a hexadecimal string for the inputs. Calls toString on the input
43 * objects to convert into a byte stream.
46 * @return SHA 256 hash of the inputs as a hexadecimal string.
49 public String generateSHA256AsHex(Object... values) throws IOException {
50 byte[] bytes = convertToBytes(values);
51 byte[] digest = messageDigest.digest(bytes);
52 StringBuilder result = new StringBuilder();
53 for (byte byt : digest) {
54 result.append(Integer.toString((byt & 0xff) + 0x100, 16).substring(1));
56 return result.toString();
59 private byte[] convertToBytes(Object... values) throws IOException {
60 try (ByteArrayOutputStream bos = new ByteArrayOutputStream(); ObjectOutput out = new ObjectOutputStream(bos)) {
61 for (Object object : values) {
62 out.writeObject(object.toString());
64 return bos.toByteArray();