Enviar mensaje de WhatsApp Java Android Studio

// HazaaZOOZ - java - Android studio - How to send whatsapp message ?
// best Answer ...              
              Intent In_Whats = new Intent(Intent.ACTION_VIEW);
              In_Whats.setData(Uri.parse(" http://api.whatsapp.com/send?phone=+99999999999&&text=Hi "));
              startActivity(In_Whats);
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