org.atmosphere.nettosphere.NettyWebSocketFragmenter Maven / Gradle / Ivy
/*
* Copyright 2008-2020 Async-IO.org
*
* 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 org.atmosphere.nettosphere;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.handler.codec.http.websocketx.BinaryWebSocketFrame;
import io.netty.handler.codec.http.websocketx.ContinuationWebSocketFrame;
import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import io.netty.handler.codec.http.websocketx.WebSocketFrame;
public class NettyWebSocketFragmenter {
private final Channel channel;
private final int maxFrameSize;
public NettyWebSocketFragmenter(Channel channel, int maxFrameSize) {
this.channel = channel;
this.maxFrameSize = maxFrameSize;
}
/**
* From RFC 6455 https://tools.ietf.org/html/rfc6455
*
* An unfragmented message consists of a single frame with the FIN bit set and an opcode other than 0.
* A fragmented message consists of a single frame with the FIN bit clear and an opcode other than 0,
* followed by zero or more frames with the FIN bit clear and the opcode set to 0, and terminated by
* a single frame with the FIN bit set and an opcode of 0.
* 0x0 denotes a continuation frame
* 0x1 denotes a text frame
* 0x2 denotes a binary frame
*/
public void write(byte[] data, int offset, int length, boolean binary) {
if (length <= maxFrameSize) {
channel.writeAndFlush(getWebSocketFrameFinal(Unpooled.wrappedBuffer(data, offset, length), binary));
} else {
channel.write(getWebSocketFrameNotFinal(Unpooled.wrappedBuffer(data, offset, maxFrameSize), binary));
int i = offset + maxFrameSize;
int lengthMinusMaxFrameSize = length - maxFrameSize;
for (; i < lengthMinusMaxFrameSize; i += maxFrameSize) {
channel.write(new ContinuationWebSocketFrame(
false, 0, Unpooled.wrappedBuffer(data, i, maxFrameSize)));
}
channel.write(new ContinuationWebSocketFrame(
true, 0, Unpooled.wrappedBuffer(data, i, length - i)));
channel.flush();
}
}
private static WebSocketFrame getWebSocketFrameFinal(ByteBuf bb, boolean binary) {
return binary ? new BinaryWebSocketFrame(bb) : new TextWebSocketFrame(bb);
}
private static WebSocketFrame getWebSocketFrameNotFinal(ByteBuf bb, boolean binary) {
return binary ? new BinaryWebSocketFrame(false, 0, bb) :
new TextWebSocketFrame(false, 0, bb);
}
}