1 /*
2 * Copyright 2012 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * https://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, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package io.netty5.handler.codec.base64;
17
18 import io.netty5.buffer.api.Buffer;
19 import io.netty5.channel.ChannelHandlerContext;
20 import io.netty5.channel.ChannelPipeline;
21 import io.netty5.handler.codec.DelimiterBasedFrameDecoder;
22 import io.netty5.handler.codec.Delimiters;
23 import io.netty5.handler.codec.MessageToMessageDecoder;
24
25 import static java.util.Objects.requireNonNull;
26
27 /**
28 * Decodes a Base64-encoded {@link Buffer} or US-ASCII {@link String}
29 * into a {@link Buffer}. Please note that this decoder must be used
30 * with a proper {@link ByteToMessageDecoder} such as {@link DelimiterBasedFrameDecoder}
31 * if you are using a stream-based transport such as TCP/IP. A typical decoder
32 * setup for TCP/IP would be:
33 * <pre>
34 * {@link ChannelPipeline} pipeline = ...;
35 *
36 * // Decoders
37 * pipeline.addLast("frameDecoder", new {@link DelimiterBasedFrameDecoder}(80, {@link Delimiters#nulDelimiter()}));
38 * pipeline.addLast("base64Decoder", new {@link Base64Decoder}());
39 *
40 * // Encoder
41 * pipeline.addLast("base64Encoder", new {@link Base64Encoder}());
42 * </pre>
43 */
44 public class Base64Decoder extends MessageToMessageDecoder<Buffer> {
45
46 private final Base64Dialect dialect;
47
48 public Base64Decoder() {
49 this(Base64Dialect.STANDARD);
50 }
51
52 public Base64Decoder(Base64Dialect dialect) {
53 requireNonNull(dialect, "dialect");
54 this.dialect = dialect;
55 }
56
57 @Override
58 public boolean isSharable() {
59 return true;
60 }
61
62 @Override
63 protected void decode(ChannelHandlerContext ctx, Buffer msg) throws Exception {
64 ctx.fireChannelRead(Base64.decode(msg, msg.readerOffset(), msg.readableBytes(), dialect));
65 }
66 }