package com.test.server;
import static org.jboss.netty.handler.codec.http.HttpHeaders.Names.CONTENT_TYPE;
import static org.jboss.netty.handler.codec.http.HttpMethod.GET;
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.BAD_REQUEST;
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.METHOD_NOT_ALLOWED;
import static org.jboss.netty.handler.codec.http.HttpResponseStatus.OK;
import static org.jboss.netty.handler.codec.http.HttpVersion.HTTP_1_1;
import java.util.concurrent.atomic.AtomicInteger;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFutureListener;
import org.jboss.netty.channel.ChannelHandlerContext;
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.handler.codec.frame.TooLongFrameException;
import org.jboss.netty.handler.codec.http.DefaultHttpChunk;
import org.jboss.netty.handler.codec.http.DefaultHttpResponse;
import org.jboss.netty.handler.codec.http.HttpChunk;
import org.jboss.netty.handler.codec.http.HttpHeaders;
import org.jboss.netty.handler.codec.http.HttpRequest;
import org.jboss.netty.handler.codec.http.HttpResponse;
import org.jboss.netty.handler.codec.http.HttpResponseStatus;
import org.jboss.netty.util.CharsetUtil;
public class HttpChunkedServerHandler extends SimpleChannelUpstreamHandler {
private static final AtomicInteger count = new AtomicInteger(0);
private void increment() {
System.out.format("online user %d\n", count.incrementAndGet());
}
private void decrement() {
if (count.get() <= 0) {
System.out.format("~online user %d\n", 0);
} else {
System.out.format("~online user %d\n", count.decrementAndGet());
}
}
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e)
throws Exception {
HttpRequest request = (HttpRequest) e.getMessage();
if (request.getMethod() != GET) {
sendError(ctx, METHOD_NOT_ALLOWED);
return;
}
sendPrepare(ctx);
increment();
}
@Override
public void channelDisconnected(ChannelHandlerContext ctx,
ChannelStateEvent e) throws Exception {
decrement();
super.channelDisconnected(ctx, e);
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e)
throws Exception {
Throwable cause = e.getCause();
if (cause instanceof TooLongFrameException) {
sendError(ctx, BAD_REQUEST);
return;
}
}
private static void sendError(ChannelHandlerContext ctx,
HttpResponseStatus status) {
HttpResponse response = new DefaultHttpResponse(HTTP_1_1, status);
response.setHeader(CONTENT_TYPE, "text/plain; charset=UTF-8");
response.setContent(ChannelBuffers.copiedBuffer(
"Failure: " + status.toString() + "\r\n", CharsetUtil.UTF_8));
// Close the connection as soon as the error message is sent.
ctx.getChannel().write(response)
.addListener(ChannelFutureListener.CLOSE);
}
private void sendPrepare(ChannelHandlerContext ctx) {
HttpResponse response = new DefaultHttpResponse(HTTP_1_1, OK);
response.setChunked(true);
response.setHeader(HttpHeaders.Names.CONTENT_TYPE,
"text/html; charset=UTF-8");
response.addHeader(HttpHeaders.Names.CONNECTION,
HttpHeaders.Values.KEEP_ALIVE);
response.setHeader(HttpHeaders.Names.TRANSFER_ENCODING,
HttpHeaders.Values.CHUNKED);
Channel chan = ctx.getChannel();
chan.write(response);
// 緩沖必須湊夠256字節，瀏覽器端才能夠正常接收 ...
StringBuilder builder = new StringBuilder();
builder.append("<html><body><script>var _ = function (msg) { parent.s._(msg, document); };</script>");
int leftChars = 256 - builder.length();
for (int i = 0; i < leftChars; i++) {
builder.append(" ");
}
writeStringChunk(chan, builder.toString());
}
private void writeStringChunk(Channel channel, String data) {
ChannelBuffer chunkContent = ChannelBuffers.dynamicBuffer(channel
.getConfig().getBufferFactory());
chunkContent.writeBytes(data.getBytes());
HttpChunk chunk = new DefaultHttpChunk(chunkContent);
channel.write(chunk);
}
}