Streaming validator that works on SAX stream.
ValidatorHandler object is not thread-safe and not reentrant. In other words, it is the application's responsibility to make sure that one
ValidatorHandler object is not used from more than one thread at any given time.
ValidatorHandler checks if the SAX events follow the set of constraints described in the associated
Schema, and additionally it may modify the SAX events (for example by adding default values, etc.)
ValidatorHandler extends from
ContentHandler, but it refines the underlying
ContentHandler in the following way:
- startElement/endElement events must receive non-null String for
qname, even though SAX allows some of them to be null. Similarly, the user-specified
ContentHandler will receive non-null Strings for all three parameters.
- Applications must ensure that
ContentHandler.endPrefixMapping(String) are invoked properly. Similarly, the user-specified
ContentHandler will receive startPrefixMapping/endPrefixMapping events. If the
ValidatorHandler introduces additional namespace bindings, the user-specified
ContentHandler will receive additional startPrefixMapping/endPrefixMapping events.
Attributes for the
ContentHandler.startElement(String,String,String,Attributes) method may or may not include xmlns* attributes.
ValidatorHandler is automatically reset every time the startDocument method is invoked.
Recognized Properties and Features
This spec defines the following feature that must be recognized by all
This feature controls how a
ValidatorHandler introduces namespace bindings that were not present in the original SAX event stream. When this feature is set to true, it must make sure that the user's
ContentHandler will see the corresponding
xmlns* attribute in the
Attributes object of the
ContentHandler.startElement(String,String,String,Attributes) callback. Otherwise,
xmlns* attributes must not be added to
Attributes that's passed to the user-specified
(Note that regardless of this switch, namespace bindings are always notified to applications through
ContentHandler.endPrefixMapping(String) methods of the
ContentHandler specified by the user.)
Note that this feature does NOT affect the way a
ValidatorHandler receives SAX events. It merely changes the way it augments SAX events.
This feature is set to
false by default.