Method send

java/lib/src/main/java/io/github/ccxt/ws/WsClient.java:556–585

Send a message over the WebSocket. Accepts String or Object (serialized to JSON). Returns a CompletableFuture that completes when the message is flushed to the network. Callers should handle the returned future to detect send failures.

(Object message)

     * Callers should handle the returned future to detect send failures.
     */
    public CompletableFuture<Void> send(Object message) {
        String json;
        if (message instanceof String s) {
            json = s;
        } else {
            try {
                json = JSON_MAPPER.writeValueAsString(message);
            } catch (Exception e) {
                json = String.valueOf(message);
            }
        }

        if (this.verbose) {
            System.out.println(getFormattedDate() +  "Sending: " + json);
        }

        if (this.channel != null && this.channel.isActive()) {
            CompletableFuture<Void> result = new CompletableFuture<>();
            this.channel.writeAndFlush(new TextWebSocketFrame(json)).addListener(future -> {
                if (future.isSuccess()) {
                    result.complete(null);
                } else {
                    result.completeExceptionally(future.cause());
                }
            });
            return result;
        }
        return CompletableFuture.failedFuture(
                new RuntimeException("WebSocket not connected: " + this.url));
    }

    /**
     * Close the WebSocket connection and reject all pending futures.