StringEchoHandler Class — netty Architecture

Source Code

testsuite/src/main/java/io/netty/testsuite/transport/socket/SocketStringEchoTest.java lines 148–209

    static class StringEchoHandler extends SimpleChannelInboundHandler<String> {
        private final boolean autoRead;
        private final Promise<Void> donePromise;
        private int dataIndex;
        volatile Channel channel;
        final AtomicReference<Throwable> exception = new AtomicReference<Throwable>();

        StringEchoHandler(boolean autoRead, Promise<Void> donePromise) {
            this.autoRead = autoRead;
            this.donePromise = donePromise;
        }

        @Override
        public void channelActive(ChannelHandlerContext ctx) throws Exception {
            channel = ctx.channel();
            if (!autoRead) {
                ctx.read();
            }
        }

        @Override
        public void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception {
            if (!data[dataIndex].equals(msg)) {
                donePromise.tryFailure(new IllegalStateException("index: " + dataIndex + " didn't match!"));
                ctx.close();
                return;
            }

            if (channel.parent() != null) {
                String delimiter = random.nextBoolean() ? "\r\n" : "\n";
                channel.write(msg + delimiter);
            }

            if (++dataIndex >= data.length) {
                donePromise.setSuccess(null);
            }
        }

        @Override
        public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
            try {
                ctx.flush();
            } finally {
                if (!autoRead) {
                    ctx.read();
                }
            }
        }

        @Override
        public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
            if (exception.compareAndSet(null, cause)) {
                donePromise.tryFailure(new IllegalStateException("exceptionCaught: " + ctx.channel(), cause));
                ctx.close();
            }
        }

        @Override
        public void channelInactive(ChannelHandlerContext ctx) throws Exception {
            donePromise.tryFailure(new IllegalStateException("channelInactive: " + ctx.channel()));
        }
    }