DiscardClientHandler.java

package org.jboss.netty.example.discard;

import java.util.logging.Level;
import java.util.logging.Logger;

import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelEvent;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.ChannelState;
import org.jboss.netty.channel.ChannelStateEvent;
import org.jboss.netty.channel.ExceptionEvent;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.channel.SimpleChannelUpstreamHandler;
import org.jboss.netty.channel.WriteCompletionEvent;

public class DiscardClientHandler extends SimpleChannelUpstreamHandler {
	
	private static final Logger logger = Logger.getLogger(DiscardClientHandler.class.getName());

	private long transferredBytes;
	
	private final byte[] content;
	
	public DiscardClientHandler(int messageSize) {
		if (messageSize <= 0) {
			throw new IllegalArgumentException("messageSize: " + messageSize);
		}
		content = new byte[messageSize];
	}
	
	public long getTransferredBytes() {
		return transferredBytes;
	}

	@Override
	public void handleUpstream(ChannelHandlerContext ctx, ChannelEvent e) throws Exception {
		if (e instanceof ChannelStateEvent) {
			if (((ChannelStateEvent) e).getState() != ChannelState.INTEREST_OPS) {
				logger.info(e.toString());
			}
		}
		super.handleUpstream(ctx, e);
	}
	
	@Override
	public void channelConnected(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {
		generateTraffic(e);
	}

	@Override
	public void channelInterestChanged(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {
		generateTraffic(e);
	}

	@Override
	public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception {
	}

	@Override
	public void writeComplete(ChannelHandlerContext ctx, WriteCompletionEvent e) throws Exception {
		transferredBytes += e.getWrittenAmount();
		System.out.println("Client transferredBytes: " + transferredBytes);
	}

	@Override
	public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) throws Exception {
		logger.log(Level.WARNING, "Unexpected exception from downstream.", e.getCause());
		e.getChannel().close();
	}

	private void generateTraffic(ChannelStateEvent e) {
		Channel channel = e.getChannel();
		while (channel.isWritable()) {
			ChannelBuffer m = nextMessage();
			if (m == null) {
				break;
			}
			channel.write(m);
		}
	}
	
	private ChannelBuffer nextMessage() {
		return ChannelBuffers.wrappedBuffer(content);
	}
}