Lately, I was trying to resolve an issue with an xsl:import statement looking for a document in from the Tomcat servers base directory (/var/lib/tomcat7). Naturally, you have to tell the transformer how to resolve the the URI -- how would it know otherise?

The API provides a way for URIs referenced from within the stylesheet instructions or within the transformation to be resolved by the calling application. This can be done by creating a class that implements the URIResolver interface, with its one method, URIResolver.resolve(java.lang.String, java.lang.String), and use this class to set the URI resolution for the transformation instructions or transformation with TransformerFactory.setURIResolver(javax.xml.transform.URIResolver) or Transformer.setURIResolver(javax.xml.transform.URIResolver). The URIResolver.resolve method takes two String arguments, the URI found in the stylesheet instructions or built as part of the transformation process, and the base URI against which the first argument will be made absolute if the absolute URI is required. The returned Source object must be usable by the transformer, as specified in its implemented features.

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