code: private int request (String encoded) throws IOException {
      refreshSignature();
      HttpPost httpPost = new HttpPost(targetURI);
      httpPost.setHeader("Content-type", "application/vnd.microsoft.servicebus.json");
      httpPost.setHeader("Authorization", signature);
      httpPost.setHeader("Host", namespaceName + ".servicebus.windows.net ");
  
      StringEntity entity = new StringEntity(encoded);
      httpPost.setEntity(entity);
  
      HttpResponse response = httpclient.execute(httpPost);
      StatusLine status = response.getStatusLine();
      HttpEntity entity2 = response.getEntity();
      // do something useful with the response body
      // and ensure it is fully consumed
      EntityUtils.consume(entity2);
  
      int returnCode = status.getStatusCode();
      if (returnCode != HttpStatus.SC_CREATED) {
        LOG.error (new IOException(status.getReasonPhrase()).toString());
        throw new IOException(status.getReasonPhrase());
      }
  
      return returnCode;
    }
docs: Send an encoded string to the Eventhub using post method