It is always a good idea to keep the buyer posted about the order shipping status. Use the CompleteSale call mark an item as shipped. You can also upload a shipment tracking number so that the buyer can track the order.
This is a sample that demonstrates how to mark an item as shipped and upload the tracking number.
/**
*
* Sample code to relist an item (with minor modifications) using the RelistFixedPriceItem call
*
* The following steps outline what needs to be done for a successfull GetTransactions and GetOrders call
*
* 1. Create an ApiContext Object
* 2. Set the auth token and target api url (Webservice endpoint)
* 3. Create an object of CompleteSaleCall.
* 4. Set the following values to the object
* OrderLineItemID
* Shipment Details
* 5. Complete the sale by calling CompleteSaleCall#completeSale()
*
*/
public class CompleteSale {
public static void completeSale() {
ApiContext apiContext = new ApiContext();
ApiLogging apiLogging = new ApiLogging();
apiContext.setApiLogging(apiLogging);
// set the server url and credentials for Sandbox
apiContext.setApiServerUrl("https://api.sandbox.ebay.com/wsapi");
ApiCredential cred = apiContext.getApiCredential();
cred.seteBayToken("YOUR TOKEN");
apiContext.setApiCredential(cred);
// If you are makding the call for UK sellers
// Set site to UK as apiContext.setSite(SiteCodeType.UK)
apiContext.setSite(SiteCodeType.US); // Set site to US