| /* |
| * Copyright 2000-2013 JetBrains s.r.o. |
| * |
| * 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. |
| */ |
| package com.intellij.util; |
| |
| import com.intellij.util.text.StringFactory; |
| import org.jetbrains.annotations.NotNull; |
| |
| /** |
| * @author maxim |
| * @since 18.07.2006 |
| */ |
| public class Base64Converter { |
| private static final char[] alphabet = { |
| 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', // 0 to 7 |
| 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', // 8 to 15 |
| 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', // 16 to 23 |
| 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', // 24 to 31 |
| 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', // 32 to 39 |
| 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', // 40 to 47 |
| 'w', 'x', 'y', 'z', '0', '1', '2', '3', // 48 to 55 |
| '4', '5', '6', '7', '8', '9', '+', '/'}; // 56 to 63 |
| |
| private static final byte[] decodeTable = { |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, |
| 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, |
| 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, |
| -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, |
| 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, |
| }; |
| |
| public static String encode(@NotNull String s) { |
| return encode(s.getBytes()); |
| } |
| |
| public static String encode(@NotNull byte[] octetString) { |
| int bits24; |
| int bits6; |
| |
| char[] out |
| = new char[((octetString.length - 1) / 3 + 1) * 4]; |
| |
| int outIndex = 0; |
| int i = 0; |
| |
| while ((i + 3) <= octetString.length) { |
| // store the octets |
| bits24 = (octetString[i++] & 0xFF) << 16; |
| bits24 |= (octetString[i++] & 0xFF) << 8; |
| bits24 |= (octetString[i++] & 0xFF); |
| |
| bits6 = (bits24 & 0x00FC0000) >> 18; |
| out[outIndex++] = alphabet[bits6]; |
| bits6 = (bits24 & 0x0003F000) >> 12; |
| out[outIndex++] = alphabet[bits6]; |
| bits6 = (bits24 & 0x00000FC0) >> 6; |
| out[outIndex++] = alphabet[bits6]; |
| bits6 = (bits24 & 0x0000003F); |
| out[outIndex++] = alphabet[bits6]; |
| } |
| |
| if (octetString.length - i == 2) { |
| // store the octets |
| bits24 = (octetString[i] & 0xFF) << 16; |
| bits24 |= (octetString[i + 1] & 0xFF) << 8; |
| |
| bits6 = (bits24 & 0x00FC0000) >> 18; |
| out[outIndex++] = alphabet[bits6]; |
| bits6 = (bits24 & 0x0003F000) >> 12; |
| out[outIndex++] = alphabet[bits6]; |
| bits6 = (bits24 & 0x00000FC0) >> 6; |
| out[outIndex++] = alphabet[bits6]; |
| |
| // padding |
| out[outIndex] = '='; |
| } |
| else if (octetString.length - i == 1) { |
| // store the octets |
| bits24 = (octetString[i] & 0xFF) << 16; |
| |
| bits6 = (bits24 & 0x00FC0000) >> 18; |
| out[outIndex++] = alphabet[bits6]; |
| bits6 = (bits24 & 0x0003F000) >> 12; |
| out[outIndex++] = alphabet[bits6]; |
| |
| // padding |
| out[outIndex++] = '='; |
| out[outIndex] = '='; |
| } |
| |
| return StringFactory.createShared(out); |
| } |
| |
| public static String decode(@NotNull String s) { |
| return new String(decode(s.getBytes())); |
| } |
| |
| public static byte[] decode(@NotNull byte[] bytes) { |
| int paddingCount = 0; |
| int realLength = 0; |
| |
| for (int i = bytes.length - 1; i >= 0; i--) { |
| if (bytes[i] > ' ') { |
| realLength++; |
| } |
| |
| if (bytes[i] == '=') { |
| paddingCount++; |
| } |
| } |
| |
| if (realLength % 4 != 0) { |
| throw new IllegalArgumentException("Incorrect length " + realLength + ". Must be a multiple of 4"); |
| } |
| final byte[] out = new byte[realLength / 4 * 3 - paddingCount]; |
| final byte[] t = new byte[4]; |
| int outIndex = 0; |
| int index = 0; |
| t[0] = t[1] = t[2] = t[3] = '='; |
| |
| for (byte c : bytes) { |
| if (c > ' ') { |
| t[index++] = c; |
| } |
| |
| if (index == 4) { |
| outIndex += decode(out, outIndex, t[0], t[1], t[2], t[3]); |
| index = 0; |
| t[0] = t[1] = t[2] = t[3] = '='; |
| } |
| } |
| |
| if (index > 0) { |
| decode(out, outIndex, t[0], t[1], t[2], t[3]); |
| } |
| return out; |
| } |
| |
| private static int decode(byte[] output, int outIndex, byte a, byte b, byte c, byte d) { |
| byte da = decodeTable[a]; |
| byte db = decodeTable[b]; |
| byte dc = decodeTable[c]; |
| byte dd = decodeTable[d]; |
| |
| if ((da == -1) || (db == -1) || ((dc == -1) && (c != '=')) || ((dd == -1) && (d != '='))) { |
| throw new IllegalArgumentException( |
| "Invalid character [" + (a & 0xFF) + ", " + (b & 0xFF) + ", " + (c & 0xFF) + ", " + (d & 0xFF) + "]"); |
| } |
| output[outIndex++] = (byte)((da << 2) | db >>> 4); |
| |
| if (c == '=') { |
| return 1; |
| } |
| output[outIndex++] = (byte)((db << 4) | dc >>> 2); |
| |
| if (d == '=') { |
| return 2; |
| } |
| output[outIndex] = (byte)((dc << 6) | dd); |
| return 3; |
| } |
| } |