WebSocketFrameHandler Class — netty Architecture

Source Code

example/src/main/java/io/netty/example/http/websocketx/server/WebSocketFrameHandler.java lines 29–54

public class WebSocketFrameHandler extends SimpleChannelInboundHandler<WebSocketFrame> {

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, WebSocketFrame frame) throws Exception {
        // ping and pong frames already handled

        if (frame instanceof TextWebSocketFrame) {
            // Send the uppercase string back.
            String request = ((TextWebSocketFrame) frame).text();
            ctx.channel().writeAndFlush(new TextWebSocketFrame(request.toUpperCase(Locale.US)));
        } else {
            String message = "unsupported frame type: " + frame.getClass().getName();
            throw new UnsupportedOperationException(message);
        }
    }

    @Override
    public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
        if (evt instanceof WebSocketServerProtocolHandler.HandshakeComplete) {
            //Channel upgrade to websocket, remove WebSocketIndexPageHandler.
            ctx.pipeline().remove(WebSocketIndexPageHandler.class);
        } else {
            super.userEventTriggered(ctx, evt);
        }
    }
}