1 /* 2 * Copyright (C) 2008 Google Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.android.mail.lib.base; 17 18 /** 19 * Static utility methods pertaining especially to byte arrays. Note that I/O-related functionality 20 * belongs in the {@code com.google.common.io} package. 21 * 22 * @author Chris Nokleberg 23 * @author Hiroshi Yamauchi 24 */ 25 public final class ByteArrays { ByteArrays()26 private ByteArrays() {} 27 28 private static final char[] HEX_DIGITS = "0123456789abcdef".toCharArray(); 29 30 /** 31 * Returns the byte array formatted as a lowercase hexadecimal string. The string will be 32 * {@code 2 * bytes.length} characters long. 33 */ toHexString(byte[] bytes)34 public static String toHexString(byte[] bytes) { 35 StringBuilder sb = new StringBuilder(2 * bytes.length); 36 for (byte b : bytes) { 37 sb.append(HEX_DIGITS[(b >> 4) & 0xf]).append(HEX_DIGITS[b & 0xf]); 38 } 39 return sb.toString(); 40 } 41 }