org.geotools.gml
Class GMLFilterDocument

java.lang.Object
  org.xml.sax.helpers.XMLFilterImpl
      org.geotools.gml.GMLFilterDocument

All Implemented Interfaces:

org.xml.sax.ContentHandler, org.xml.sax.DTDHandler, org.xml.sax.EntityResolver, org.xml.sax.ErrorHandler, org.xml.sax.XMLFilter, org.xml.sax.XMLReader

public class GMLFilterDocument

extends org.xml.sax.helpers.XMLFilterImpl

LEVEL1 saxGML4j GML filter: Sends basic alerts for GML types to GMLFilterGeometry.

This filter separates and passes GML events to a GMLHandlerGeometry. The main simplification that it performs is to pass along coordinates as an abstracted method call, regardless of their notation in the GML (Coord vs. Coordinates). This call turns the coordinates into doubles and makes sure that it distinguishes between 2 and 3 value coordinates.

The filter also handles some more subtle processing, including handling different delimiters (decimal, coordinate, tuple) that may be used by more outlandish GML generators.

Version:

$Id: GMLFilterDocument.java 17701 2006-01-23 00:00:51Z desruisseaux $

Author:

Rob Hranac, Vision for New York

Constructor Summary

GMLFilterDocument(GMLHandlerGeometry parent)
Constructor with parent.

Method Summary

void	characters(char[] ch, int start, int length) Reads the only internal characters read by pure GML parsers, which are coordinates.
void	endElement(java.lang.String namespaceURI, java.lang.String localName, java.lang.String qName) Checks for GML element end and - if not a coordinates element - sends it directly on down the chain to the appropriate parent handler.
void	startElement(java.lang.String namespaceURI, java.lang.String localName, java.lang.String qName, org.xml.sax.Attributes atts) Checks for GML element start and - if not a coordinates element - sends it directly on down the chain to the appropriate parent handler.

Methods inherited from class org.xml.sax.helpers.XMLFilterImpl

endDocument, endPrefixMapping, error, fatalError, getContentHandler, getDTDHandler, getEntityResolver, getErrorHandler, getFeature, getParent, getProperty, ignorableWhitespace, notationDecl, parse, parse, processingInstruction, resolveEntity, setContentHandler, setDocumentLocator, setDTDHandler, setEntityResolver, setErrorHandler, setFeature, setParent, setProperty, skippedEntity, startDocument, startPrefixMapping, unparsedEntityDecl, warning

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GMLFilterDocument

public GMLFilterDocument(GMLHandlerGeometry parent)

Constructor with parent.

Parameters:

parent - Parent of the filter: must implement GMLHandlerGeometry.

Method Detail

startElement

public void startElement(java.lang.String namespaceURI,
                         java.lang.String localName,
                         java.lang.String qName,
                         org.xml.sax.Attributes atts)
                  throws org.xml.sax.SAXException

Checks for GML element start and - if not a coordinates element - sends it directly on down the chain to the appropriate parent handler. If it is a coordinates (or coord) element, it uses internal methods to set the current state of the coordinates reader appropriately.

Modified by Sean Geoghegan to create new StringBuffers when entering a coord or coordinate element.

Parameters:

namespaceURI - The namespace of the element.

localName - The local name of the element.

qName - The full name of the element, including namespace prefix.

atts - The element attributes.

Throws:

org.xml.sax.SAXException - Some parsing error occurred while reading coordinates.

characters

public void characters(char[] ch,
                       int start,
                       int length)
                throws org.xml.sax.SAXException

Reads the only internal characters read by pure GML parsers, which are coordinates. These coordinates are sent to the coordinates reader class, which interprets them appropriately, depending on its current state.

Modified by Sean Geoghegan to append character data to buffer when inside a coordinate or coord element. SAX doesn't guarentee that all the character data of an element will be passed to the character method in one call, it may be split up into chunks.

Parameters:

ch - Raw coordinate string from the GML document.

start - Beginning character position of raw coordinate string.

length - Length of the character string.

Throws:

org.xml.sax.SAXException - Some parsing error occurred while reading coordinates.

endElement

public void endElement(java.lang.String namespaceURI,
                       java.lang.String localName,
                       java.lang.String qName)
                throws org.xml.sax.SAXException

Checks for GML element end and - if not a coordinates element - sends it directly on down the chain to the appropriate parent handler. If it is a coordinates (or coord) element, it uses internal methods to set the current state of the coordinates reader appropriately.

Modified by Sean Geoghegan. When we reach the end of a coord or coordinate element, then the buffer is passed to the handler for processing.

Parameters:

namespaceURI - The namespace of the element.

localName - The local name of the element.

qName - The full name of the element, including namespace prefix.

Throws:

org.xml.sax.SAXException - Some parsing error occurred while reading coordinates.