Parser provides an API for parsing XML documents and building or augmeting the corresponding DOM document tree.
A Parser instance is obtained from the ImplementationLS interface by invoking its createDOMParser method. This implementation also allows the applications to install an error handler (useful extensions to the DOM specification).
While parsing an input source, errors are reported to the application through the error handler. For this you have to set the Error Handler first.
This interface is a binding to Xerces' DOMBuilder class. It offers an experimental and incomplete access to the DOMParser interface as described in DOM Level 3 Load and Save, but as this document has not yet achieved the status of a Recommendation this Binding does not offer much more than the methods needed to parse XML documents. This will change as soon as the implementation and standardization processes are completed.
The methods concerning the features will probably be outsourced to a specific configuration interface, so they may be regarded as Implementation- or Binding-specific right now. A list of features that may be set is given in the Xerces documentation (be reminded that the binding as it is now only supports synchronous parsers).