@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
e.getCause().printStackTrace();
Channel ch = e.getChannel();
ch.close();
}
/** Something has happened to one of the open channels. Just shut it down. */
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
e.getChannel().close();
}