org.jboss.netty.handler.codec.http.websocketx.WebSocket00FrameEncoder Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of netty Show documentation

The Netty project is an effort to provide an asynchronous event-driven network application framework and tools for rapid development of maintainable high performance and high scalability protocol servers and clients. In other words, Netty is a NIO client server framework which enables quick and easy development of network applications such as protocol servers and clients. It greatly simplifies and streamlines network programming such as TCP and UDP socket server.

There is a newer version: 4.0.0.Alpha8

Show newest version

/*
 * 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 org.jboss.netty.handler.codec.http.websocketx;

import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelHandler.Sharable;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.handler.codec.oneone.OneToOneEncoder;

/**
 * Encodes a {@link WebSocketFrame} into a {@link ChannelBuffer}.
 * 
 * For the detailed instruction on adding add Web Socket support to your HTTP server, take a look into the
 * WebSocketServer example located in the {@code org.jboss.netty.example.http.websocket} package.
 *
 * @apiviz.landmark
 * @apiviz.uses org.jboss.netty.handler.codec.http.websocket.WebSocketFrame
 */
@Sharable
public class WebSocket00FrameEncoder extends OneToOneEncoder {

    @Override
    protected Object encode(ChannelHandlerContext ctx, Channel channel, Object msg) throws Exception {
        if (msg instanceof WebSocketFrame) {
            WebSocketFrame frame = (WebSocketFrame) msg;
            if (frame instanceof TextWebSocketFrame) {
                // Text frame
                ChannelBuffer data = frame.getBinaryData();
                ChannelBuffer encoded = channel.getConfig().getBufferFactory()
                        .getBuffer(data.order(), data.readableBytes() + 2);
                encoded.writeByte((byte) 0x00);
                encoded.writeBytes(data, data.readerIndex(), data.readableBytes());
                encoded.writeByte((byte) 0xFF);
                return encoded;
            } else if (frame instanceof CloseWebSocketFrame) {
                // Close frame
                ChannelBuffer data = frame.getBinaryData();
                ChannelBuffer encoded = channel.getConfig().getBufferFactory().getBuffer(data.order(), 2);
                encoded.writeByte((byte) 0xFF);
                encoded.writeByte((byte) 0x00);
                return encoded;
            } else {
                // Binary frame
                ChannelBuffer data = frame.getBinaryData();
                int dataLen = data.readableBytes();
                ChannelBuffer encoded = channel.getConfig().getBufferFactory().getBuffer(data.order(), dataLen + 5);

                // Encode type.
                encoded.writeByte((byte) 0x80);

                // Encode length.
                int b1 = dataLen >>> 28 & 0x7F;
                int b2 = dataLen >>> 14 & 0x7F;
                int b3 = dataLen >>> 7 & 0x7F;
                int b4 = dataLen & 0x7F;
                if (b1 == 0) {
                    if (b2 == 0) {
                        if (b3 == 0) {
                            encoded.writeByte(b4);
                        } else {
                            encoded.writeByte(b3 | 0x80);
                            encoded.writeByte(b4);
                        }
                    } else {
                        encoded.writeByte(b2 | 0x80);
                        encoded.writeByte(b3 | 0x80);
                        encoded.writeByte(b4);
                    }
                } else {
                    encoded.writeByte(b1 | 0x80);
                    encoded.writeByte(b2 | 0x80);
                    encoded.writeByte(b3 | 0x80);
                    encoded.writeByte(b4);
                }

                // Encode binary data.
                encoded.writeBytes(data, data.readerIndex(), dataLen);
                return encoded;
            }
        }
        return msg;
    }
}