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You can use the JAXB Unmarshaller interface to inflate an XML document into a java object or to deserialize java objects from xml. This sample illustrates the use of JAVA JAXB framework to unzip the file returned in downloadFile API
and unmarshal the Merchant Data xml document that based on Merchant Data Schema.
To run this program, you will need to first generate java classes that represent the Marchant Data Schema. Pleaes refer to the construct LMS data files with eBay Merchant Data Schema in JAVA kb for the codeGen ant script for the same.
Also, you can check the attached Java source code for the implementation of the BulkDataExchangeResponse xml for ReviseFixedPriceItem call.