Enviar WhatsApp con Java y HttpClient: ejemplo completo

cURL

curl -X POST https://api.zapzapapi.com/api/v1/SEU_INSTANCE_ID/send/text \
  -H "Content-Type: application/json" \
  -H "x-api-key: SUA_API_KEY" \
  -H "x-api-secret: SEU_API_SECRET" \
  -d '{"number":"5511999999999","text":"Olá! Teste de envio com Java."}'

Java

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Duration;

public class EnviarWhatsApp {
    static final HttpClient HTTP = HttpClient.newBuilder()
            .connectTimeout(Duration.ofSeconds(10))
            .build();

    static String escapar(String s) {
        return s.replace("\\", "\\\\").replace("\"", "\\\"").replace("\n", "\\n");
    }

    public static void main(String[] args) throws Exception {
        String instancia = System.getenv("ZAPZAP_INSTANCE_ID");
        String url = "https://api.zapzapapi.com/api/v1/" + instancia + "/send/text";

        String json = """
                {"number":"5511999999999","text":"%s"}
                """.formatted(escapar("Olá! Seu pedido saiu para entrega."));

        HttpRequest req = HttpRequest.newBuilder(URI.create(url))
                .timeout(Duration.ofSeconds(30))
                .header("Content-Type", "application/json")
                .header("x-api-key", System.getenv("ZAPZAP_API_KEY"))
                .header("x-api-secret", System.getenv("ZAPZAP_API_SECRET"))
                .POST(HttpRequest.BodyPublishers.ofString(json))
                .build();

        HttpResponse<String> res = HTTP.send(req, HttpResponse.BodyHandlers.ofString());
        if (res.statusCode() >= 300) {
            throw new IllegalStateException("Failed " + res.statusCode() + ": " + res.body());
        }
        System.out.println(res.body());
    }
}

Java

static String post(String caminho, String json) throws Exception {
    String url = "https://api.zapzapapi.com/api/v1/" + System.getenv("ZAPZAP_INSTANCE_ID") + caminho;
    HttpRequest req = HttpRequest.newBuilder(URI.create(url))
            .timeout(Duration.ofSeconds(30))
            .header("Content-Type", "application/json")
            .header("x-api-key", System.getenv("ZAPZAP_API_KEY"))
            .header("x-api-secret", System.getenv("ZAPZAP_API_SECRET"))
            .POST(HttpRequest.BodyPublishers.ofString(json))
            .build();
    HttpResponse<String> res = HTTP.send(req, HttpResponse.BodyHandlers.ofString());
    if (res.statusCode() >= 300) {
        throw new IllegalStateException("Failed " + res.statusCode() + ": " + res.body());
    }
    return res.body();
}

static String enviarDocumento(String numero, String urlPdf, String nome, String legenda) throws Exception {
    String json = "{\"number\":\"" + numero + "\",\"type\":\"document\",\"file\":\"" + urlPdf
            + "\",\"docName\":\"" + nome + "\",\"text\":\"" + escapar(legenda) + "\"}";
    return post("/send/media", json);
}

Java

HTTP.sendAsync(req, HttpResponse.BodyHandlers.ofString())
    .thenApply(res -> {
        if (res.statusCode() >= 300) {
            throw new IllegalStateException("Failed " + res.statusCode() + ": " + res.body());
        }
        return res.body();
    })
    .thenAccept(corpo -> System.out.println("sent: " + corpo))
    .exceptionally(e -> {
        System.err.println("error: " + e.getMessage());
        return null;
    });

Java

@Service
public class ZapZapService {
    private final RestClient rest;

    public ZapZapService(@Value("${zapzap.instance-id}") String instancia,
                         @Value("${zapzap.api-key}") String key,
                         @Value("${zapzap.api-secret}") String secret) {
        this.rest = RestClient.builder()
                .baseUrl("https://api.zapzapapi.com/api/v1/" + instancia)
                .defaultHeader("x-api-key", key)
                .defaultHeader("x-api-secret", secret)
                .build();
    }

    public String enviarTexto(String numero, String texto) {
        return rest.post().uri("/send/text")
                .contentType(MediaType.APPLICATION_JSON)
                .body(Map.of("number", numero, "text", texto))
                .retrieve()
                .body(String.class);
    }
}

Java

static String verificar(java.util.List<String> numeros) throws Exception {
    String lista = numeros.stream().map(n -> "\"" + n + "\"").collect(java.util.stream.Collectors.joining(","));
    return post("/chat/check", "{\"numbers\":[" + lista + "]}");
}

Java

static void enviarLista(java.util.Map<String, String> contatos) throws InterruptedException {
    java.util.concurrent.Semaphore limite = new java.util.concurrent.Semaphore(3);
    try (var pool = java.util.concurrent.Executors.newVirtualThreadPerTaskExecutor()) {
        contatos.forEach((numero, texto) -> pool.submit(() -> {
            try {
                limite.acquire();
                String json = "{\"number\":\"" + numero + "\",\"text\":\"" + escapar(texto) + "\"}";
                post("/send/text", json);
                Thread.sleep(2000 + (long) (Math.random() * 4000));
            } catch (Exception e) {
                System.err.println("failed for " + numero + ": " + e.getMessage());
            } finally {
                limite.release();
            }
            return null;
        }));
    }
}