10 XSLT or XML, XSL Transformation Interview Questions and Answers

XSLT stands for XML style sheet transformation and it as XML technology used to transform one XML into another XML or HTML format.  XML and XSLT interview questions are commonly asked Java developers, who happen to use XML in their projects and mentioned XSLT as a key skill in their resumes. Given XML’s popularity as a data transfer protocol, many systems in the middle and back-office space use XML messages to transfer trade details, for example, Bookings, Settlement, and Confirmation systems use it as data exchange protocol. Since each of these systems performs some normalization, enrichment, and transformation on incoming trade messages, they use XSLT for that transformation.

How to compare two XML files in Java - XMLUnit Example

The XMLUnit library can be used to compare two XML files in Java. Similar to JUnit, XMLUnit can also be used to test XML files for comparison by extending the XMLTestcase class. It is a rich library and provides a detailed comparison of XML files. Btw, comparing XML is completely different than comparing String in Java or comparing objects using equals(), as two XML which contains different comments and whitespace can be equals, which is not true for String or character comparison. Also while comparing XML files, it's very important to know exactly which content or part is different and XMLUnit not only shows the content which is different but also the XPath of elements which is getting compared.

JAXB Date Format Example using Annotation | Java Date to XML DateTime String Conversion

One of the common problem while marshaling Java object to XML String using JAXB is the default format of date and time provided by JAXB. When JAXB converts any Date type object or XMLGregorianCalendar to XML String, precisely xsd:dateTime element, it by default prints unformatted date e.g. 2012-05-17T09:20:00-04:30. Since most of the real world, Java application has a requirement to print date in a particular format like dd-MM-yyyy or include date and time in format dd-MM-yyyy HH:mm:ss, it becomes a problem. Thankfully, JAXB is very extensible and provides hooks and adapters to customize marshaling and unmarshaling process. You can define an extension of XmlAdapter to control and customize marshaling and unmarshaling or any Java type depending upon yours need.