| /* |
| * 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 flex.messaging.util; |
| |
| /** |
| * Code to read and write Base64-encoded text. |
| * Fairly special-purpose, not quite ready for |
| * general streaming as they don't let you |
| * drain less than everything that is currently |
| * available. |
| * |
| * |
| */ |
| public class Base64 |
| { |
| private static final char alphabet[] = |
| { |
| 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', |
| 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', |
| 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', |
| 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', |
| 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', |
| 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', |
| 'w', 'x', 'y', 'z', '0', '1', '2', '3', |
| '4', '5', '6', '7', '8', '9', '+', '/' |
| }; |
| |
| private static final int inverse[] = |
| { |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 62, 64, 64, 64, 63, |
| 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 64, 64, 64, 64, 64, 64, |
| 64, 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, 64, 64, 64, 64, 64, |
| 64, 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, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64 |
| }; |
| /** |
| * |
| */ |
| |
| public static class Decoder |
| { |
| private int filled = 0; |
| private byte data[]; |
| private int count = 0; |
| private int work[] = {0, 0, 0, 0}; |
| |
| |
| public Decoder() |
| { |
| data = new byte[256]; |
| } |
| |
| public void decode(String encoded) |
| { |
| int estimate = 1 + encoded.length() * 3 / 4; |
| |
| if (filled + estimate > data.length) |
| { |
| int length = data.length * 2; |
| while (length < filled + estimate) |
| { |
| length *= 2; |
| } |
| byte[] newdata = new byte[length]; |
| |
| System.arraycopy(data, 0, newdata, 0, filled); |
| data = newdata; |
| } |
| |
| for (int i = 0; i < encoded.length(); ++i) |
| { |
| char c = encoded.charAt(i); |
| |
| if (c == '=') |
| work[count++] = -1; |
| else if (inverse[c] != 64) |
| work[count++] = inverse[c]; |
| else |
| continue; |
| |
| if (count == 4) |
| { |
| count = 0; |
| data[filled++] = (byte)((work[0] << 2) | ((work[1] & 0xff) >> 4)); |
| |
| if (work[2] == -1) |
| break; |
| |
| data[filled++] = (byte)((work[1] << 4) | ((work[2] & 0xff) >> 2)); |
| |
| if (work[3] == -1) |
| break; |
| |
| data[filled++] = (byte)((work[2] << 6) | work[3]); |
| } |
| |
| } |
| } |
| |
| public byte[] drain() |
| { |
| byte[] r = new byte[filled]; |
| System.arraycopy(data, 0, r, 0, filled); |
| filled = 0; |
| return r; |
| } |
| |
| public byte[] flush() throws IllegalStateException |
| { |
| if (count > 0) |
| throw new IllegalStateException("a partial block (" + count + " of 4 bytes) was dropped, decoded data is probably truncated!"); |
| return drain(); |
| } |
| |
| public void reset() |
| { |
| count = 0; |
| filled = 0; |
| } |
| |
| } |
| |
| /** |
| * |
| */ |
| public static class Encoder |
| { |
| private int work[] = {0, 0, 0}; |
| private int count = 0; |
| private int line = 0; |
| private StringBuffer output; |
| |
| public Encoder(int size) |
| { |
| output = new StringBuffer(size); |
| } |
| |
| private void encodeBlock() |
| { |
| output.append(alphabet[(work[0] & 0xFF) >> 2]); |
| output.append(alphabet[((work[0] & 0x03) << 4) | ((work[1] & 0xF0) >> 4)]); |
| if (count > 1) |
| output.append(alphabet[((work[1] & 0x0F) << 2) | ((work[2] & 0xC0) >> 6)]); |
| else |
| output.append('='); |
| |
| if (count > 2) |
| output.append(alphabet[work[2] & 0x3F]); |
| else |
| output.append('='); |
| |
| if ((line += 4) == 76) |
| { |
| output.append('\n'); |
| line = 0; |
| } |
| } |
| |
| public void encode(byte[] data) |
| { |
| encode(data, 0, data.length); |
| } |
| |
| public void encode(byte[] data, int offset, int length) |
| { |
| int plainIndex = offset; |
| |
| while (plainIndex < (offset + length)) |
| { |
| work[count] = data[plainIndex]; |
| count++; |
| |
| if (count == work.length || ((offset + length) - plainIndex) == 1) |
| { |
| encodeBlock(); |
| count = 0; |
| work[0] = 0; |
| work[1] = 0; |
| work[2] = 0; |
| } |
| plainIndex++; |
| } |
| } |
| |
| public String drain() |
| { |
| String r = output.toString(); |
| output.setLength(0); |
| return r; |
| } |
| |
| public String flush() |
| { |
| if (count > 0) |
| encodeBlock(); |
| |
| String r = drain(); |
| count = 0; |
| line = 0; |
| work[0] = 0; |
| work[1] = 0; |
| work[2] = 0; |
| return r; |
| } |
| |
| |
| } |
| } |