XSLT (Extensible Stylesheet Language Transformations) is used to transform XML files into other formats like HTML format. There are many XSLT processors (libraries) available to be used in Java for XSLT transformation. These libraries can be used from a Java application like JSP/Servlet to read a XML file and to transform it into a HTML.
An XSLT processor takes two inputs: an XML file and an XSLT stylesheet.
For this post, I have chosen Xalan-Java library for the transformation.