io.netty.handler.codec.base64.Base64Decoder Maven / Gradle / Ivy
/*
* Copyright 2012 The Netty Project
*
* The Netty Project 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 io.netty.handler.codec.base64;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandler.Sharable;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPipeline;
import io.netty.handler.codec.ByteToMessageDecoder;
import io.netty.handler.codec.DelimiterBasedFrameDecoder;
import io.netty.handler.codec.Delimiters;
import io.netty.handler.codec.MessageToMessageDecoder;
/**
* Decodes a Base64-encoded {@link ByteBuf} or US-ASCII {@link String}
* into a {@link ByteBuf}. Please note that this decoder must be used
* with a proper {@link ByteToMessageDecoder} such as {@link DelimiterBasedFrameDecoder}
* if you are using a stream-based transport such as TCP/IP. A typical decoder
* setup for TCP/IP would be:
*
* {@link ChannelPipeline} pipeline = ...;
*
* // Decoders
* pipeline.addLast("frameDecoder", new {@link DelimiterBasedFrameDecoder}(80, {@link Delimiters#nulDelimiter()}));
* pipeline.addLast("base64Decoder", new {@link Base64Decoder}());
*
* // Encoder
* pipeline.addLast("base64Encoder", new {@link Base64Encoder}());
*
*/
@Sharable
public class Base64Decoder extends MessageToMessageDecoder {
private final Base64Dialect dialect;
public Base64Decoder() {
this(Base64Dialect.STANDARD);
}
public Base64Decoder(Base64Dialect dialect) {
if (dialect == null) {
throw new NullPointerException("dialect");
}
this.dialect = dialect;
}
@Override
protected Object decode(ChannelHandlerContext ctx, ByteBuf msg) throws Exception {
return Base64.decode(msg, msg.readerIndex(), msg.readableBytes(), dialect);
}
}