Java tutorial
/* * Copyright 2013 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.http.websocketx; import io.netty.buffer.ByteBuf; import io.netty.channel.ChannelPipeline; import io.netty.handler.codec.MessageAggregator; import io.netty.handler.codec.TooLongFrameException; /** * Handler that aggregate fragmented WebSocketFrame's. * * Be aware if PING/PONG/CLOSE frames are send in the middle of a fragmented {@link WebSocketFrame} they will * just get forwarded to the next handler in the pipeline. */ public class WebSocketFrameAggregator extends MessageAggregator<WebSocketFrame, WebSocketFrame, ContinuationWebSocketFrame, WebSocketFrame> { /** * Creates a new instance * * @param maxContentLength If the size of the aggregated frame exceeds this value, * a {@link TooLongFrameException} is thrown. */ public WebSocketFrameAggregator(int maxContentLength) { super(maxContentLength); } @Override protected boolean isStartMessage(WebSocketFrame msg) throws Exception { return msg instanceof TextWebSocketFrame || msg instanceof BinaryWebSocketFrame; } @Override protected boolean isContentMessage(WebSocketFrame msg) throws Exception { return msg instanceof ContinuationWebSocketFrame; } @Override protected boolean isLastContentMessage(ContinuationWebSocketFrame msg) throws Exception { return isContentMessage(msg) && msg.isFinalFragment(); } @Override protected boolean isAggregated(WebSocketFrame msg) throws Exception { if (msg.isFinalFragment()) { return !isContentMessage(msg); } return !isStartMessage(msg) && !isContentMessage(msg); } @Override protected boolean isContentLengthInvalid(WebSocketFrame start, int maxContentLength) { return false; } @Override protected Object newContinueResponse(WebSocketFrame start, int maxContentLength, ChannelPipeline pipeline) { return null; } @Override protected boolean closeAfterContinueResponse(Object msg) throws Exception { throw new UnsupportedOperationException(); } @Override protected boolean ignoreContentAfterContinueResponse(Object msg) throws Exception { throw new UnsupportedOperationException(); } @Override protected WebSocketFrame beginAggregation(WebSocketFrame start, ByteBuf content) throws Exception { if (start instanceof TextWebSocketFrame) { return new TextWebSocketFrame(true, start.rsv(), content); } if (start instanceof BinaryWebSocketFrame) { return new BinaryWebSocketFrame(true, start.rsv(), content); } // Should not reach here. throw new Error(); } }