The following java files need are included in the downloaded zip file:
 
 

Java File	Comment
TrackingHolder.java	Contains all details of a Shipment. The shipment could have been done by any carrier like Fedex, DHL,UPS etc
TrackingDefault.java	Represents default tracking informations
DHLTrackParser.java	The XML parser program that parses the XML response from DHL server
QueryDHL.java	Connects to the DHL server and get the tracking reposnse as a single XML string. It calls the DHLTrackParser to parse the string.
DHLSummaryRecord.java	Represents the summary of the shipment
DHLServiceEvent.java	Represents a DHL shipment event.

The file "file.properties" represents a ResourceBundle that provides details of the DHL tracking URI, Language, Company name etc.
 

Testing:
In the directory where u have unzipped do the following:

Compiling:
javac -classpath .;xerces.jar;xml4j.jar QueryDHL.java

Running:
java -classpath .;xerces.jar;xml4j.jar QueryDHL

Make sure that u enter a valid AirBill Number for DHL. A DHL Airbill is valid for 90 days from date of shipment as per DHLTrackingAPI.doc .