SAX
The SAX API provides a procedural approach to parsing an XML file. As a SAX parser iterates through an XML file, it performs callbacks to a user-specified object. These calls indicate the start or end of an element, the presence of character data, and other significant events during the life of the parser.
SAX doesn’t provide random access to the structure of the XML file; each tag must be handled as it is encountered by the browser. This means that SAX provides a relatively fast and efficient method of parsing. Because the SAX parser deals with only one element at a time, implementations can be extremely memory-efficient, making it often the only reasonable choice for dealing with particularly large files.
SAX Handlers
The SAX API allows you to create objects that handle
XML parsing events, by implementing the org.xml.sax.ContentHandler
, org.xml.sax.ErrorHandler
, and org.xml.sax.DTDHandler
interfaces.[32] Processing a document with SAX involves passing a
handler implementation to the parser and calling the parse()
method of SAXParser
. The parser will read the
contents of the XML file, calling the appropriate method on the
handler when significant events (such as the start of a tag) occur.
All handler methods may throw a SAXException
in the event of an
error.
We’ll take a look at the ContentHandler
, the ErrorHandler
, and the generic but useful
DefaultHandler
interfaces
next.
ContentHandler
Most, if not all, SAX applications implement the
ContentHandler
interface. The SAX parser ...
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