Here you can find the source of sha1hash(String key)
static String sha1hash(String key)
//package com.java2s; /**/* w ww .j a v a 2 s . c o m*/ * Copyright 2010-present Facebook. * * Licensed 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. */ import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; public class Main { private static final String HASH_ALGORITHM_SHA1 = "SHA-1"; static String sha1hash(String key) { return hashWithAlgorithm(HASH_ALGORITHM_SHA1, key); } static String sha1hash(byte[] bytes) { return hashWithAlgorithm(HASH_ALGORITHM_SHA1, bytes); } private static String hashWithAlgorithm(String algorithm, String key) { return hashWithAlgorithm(algorithm, key.getBytes()); } private static String hashWithAlgorithm(String algorithm, byte[] bytes) { MessageDigest hash; try { hash = MessageDigest.getInstance(algorithm); } catch (NoSuchAlgorithmException e) { return null; } return hashBytes(hash, bytes); } private static String hashBytes(MessageDigest hash, byte[] bytes) { hash.update(bytes); byte[] digest = hash.digest(); StringBuilder builder = new StringBuilder(); for (int b : digest) { builder.append(Integer.toHexString((b >> 4) & 0xf)); builder.append(Integer.toHexString((b >> 0) & 0xf)); } return builder.toString(); } }