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 com.aliyun.oss.urlsign.common.utils; //import android.util.Base64; import org.apache.commons.codec.binary.Base64; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; /** * Base64?copyapache codec ??? */ public class BinaryUtil { private static final char[] HEX_DIGITS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' }; public static String toBase64String(byte[] binaryData) { // return Base64.encodeToString(binaryData,Base64.DEFAULT); return new String(Base64.encodeBase64(binaryData)); } public static byte[] fromBase64String(String base64String) { // return Base64.decode(base64String,Base64.DEFAULT); return Base64.decodeBase64(base64String); } public static byte[] calculateMd5(byte[] binaryData) { MessageDigest messageDigest = null; try { messageDigest = MessageDigest.getInstance("MD5"); } catch (NoSuchAlgorithmException e) { throw new RuntimeException("MD5 algorithm not found."); } messageDigest.update(binaryData); return messageDigest.digest(); } public static String encodeMD5(byte[] binaryData) { byte[] md5Bytes = calculateMd5(binaryData); int len = md5Bytes.length; char buf[] = new char[len * 2]; for (int i = 0; i < len; i++) { buf[i * 2] = HEX_DIGITS[(md5Bytes[i] >>> 4) & 0x0f]; buf[i * 2 + 1] = HEX_DIGITS[md5Bytes[i] & 0x0f]; } return new String(buf); } }