org.geotools.renderer.chart
Class ChartGraphicFactory

Object
  ChartGraphicFactory

All Implemented Interfaces:

ExternalGraphicFactory

public class ChartGraphicFactory
extends Object
implements ExternalGraphicFactory

Parses Google charts like requests into various kinds of charts.

Underlying implementation is based on Eastwood charts and JFreeChart

And example of a valid symbolizer use in SLD is:

 <ExternalGraphic>
   <OnlineResource xlink:href="http://chart?cht=p&amp;chl=male|female&amp;chd=t:${100 * male / (male + female)},${100 * female / (male + female)}&amp;chs=200x100&amp;chf=bg,s,FFFFFF00"/>
   <Format>application/chart</Format>
 </ExternalGraphic>
 

This request will generate a pie chart representing the percentages of female and male population using attribute features and CQL expression to buid the percentage value to be used.

For details on the URL format documentation refer to the online Google charts API.

Also mind Eastwood does not implement all of the Google charts API, for example, Venn diagram and spider diagrams are not supported. Check on the Eastwood project pages for details.

Since:

2.5.6

Field Summary

static String

FORMAT

Constructor Summary

ChartGraphicFactory()

Method Summary

Icon	getIcon(Feature feature, Expression urlExpression, String format, int size) Turns the specified URL into an Icon, eventually using the Feature attributes to evaluate CQL expressions embedded in the url.

Methods inherited from class Object

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

Field Detail

FORMAT

public static final String FORMAT

See Also:

Constant Field Values

Constructor Detail

ChartGraphicFactory

public ChartGraphicFactory()

Method Detail

getIcon

public Icon getIcon(Feature feature,
                    Expression urlExpression,
                    String format,
                    int size)
             throws Exception

Description copied from interface: ExternalGraphicFactory

Turns the specified URL into an Icon, eventually using the Feature attributes to evaluate CQL expressions embedded in the url.
The size parameter defines the size of the image (so that vector based symbols can be drawn at the specified size directly), or may be zero or negative if the size was not specified (in that case the "natural" size of the image will be used, which is the size in pixels for raster images, and 16 for any format that does not have a specific size, according to the SLD spec).
null will be returned if this factory cannot handle the provided url.

Specified by:

getIcon in interface ExternalGraphicFactory

Throws:

Exception