android app to send whatsapp message programmatically code example

Example: send whatsapp message java android studio

//Java / Android_Studio : 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);