// Construct the client
OkHttpClient client = new OkHttpClient();

// Create the URL
HttpUrl url = new HttpUrl.Builder()
    .scheme("https")
    .host("sandbox.ebsco.io")
    .addPathSegment("rm")
    .addPathSegment("rmaccounts")
    .addPathSegment(CUSTID)
    .addPathSegment("holdings")
    .build();

// Build the body       
MediaType mediaType = MediaType.parse("application/octet-stream");
RequestBody body = RequestBody.create(mediaType, "");

// Build the request
Request request = new Request.Builder()
    .url(url)
    .post(body)
    .addHeader("cache-control", "no-cache")
    .addHeader("x-api-key", APIKEY)
    .addHeader("content-type", "application/json")
    .build();

// Send the request
Response response = client.newCall(request).execute();

var host = "https://sandbox.ebsco.io/rm/rmaccounts/";
var pathsega = "/holdings";

// Packages POST Sample
// Create the Request
var urlstr = host + CUSTID + pathsega;

var settings = {
  "async": true,
  "crossDomain": true,
  "url": urlstr,
  "method": "POST",
  "headers": {
    "x-api-key": APIKEY,
    "content-type": "application/json"
  },
  "data": ""
}

// Send the Request
$.ajax(settings).done(function (response) {
  console.log(response);
});

# Form the URL 
urlstr = File.join('https://', 'sandbox.ebsco.io', 'rm/rmaccounts', CUSTID, 'holdings')
url = URI(urlstr)

# Create the HTTP object
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
http.verify_mode = OpenSSL::SSL::VERIFY_NONE

# Create the request
request = Net::HTTP::Post.new(url)
request["x-api-key"] = APIKEY
request["content-type"] = 'application/json'
request["cache-control"] = 'no-cache'

# Send the request
response = http.request(request)

# Form the URL
url = ''.join(['/rm','/rmaccounts/', CUSTID, '/holdings'])

# Create Connection Instance
conn = http.client.HTTPSConnection("sandbox.ebsco.io")

# Payload
payload = ""

# Create the Request Headers
headers = {
    'x-api-key': APIKEY,
    'content-type': "application/json"
    }

# Send Request  
conn.request("POST", url, payload, headers)