wapim-java-OkHttp.java

OkHttpClient client = new OkHttpClient().newBuilder()
  .build();
MediaType mediaType = MediaType.parse("text/plain");
RequestBody body = RequestBody.create(mediaType, "{\n\t\"phone_number\": \"RECIPIENT_NUMBER\",\n\t\"message\": \"hello\"\n}");
Request request = new Request.Builder()
  .url("https://api.wapim.io/api/v1/whatsapp/message/text")
  .method("POST", body)
  .addHeader("token", "YOUR_WAPIM_TOKEN")
  .build();
Response response = client.newCall(request).execute();

wapim-java-Unirest.java

Unirest.setTimeouts(0, 0);
HttpResponse<String> response = Unirest.post("https://api.wapim.io/api/v1/whatsapp/message/text";)
.header("token", "YOUR_WAPIM_TOKEN")
.body("{\n\t\"phone_number\": \"RECIPIENT_NUMBER\",\n\t\"message\": \"hello\"\n}")
.asString();