You need to "register" the function in META_INF/servies as described in the function tutorial. It will need to be loaded in the same classloader as geotools for the gt-main module FunctionFinder to see it.
There is a geotools FunctionFactory implementation that scans all the functions defined in META_INF/services and provides them to the library (including the renderer). You can also take a larger gulp and register your own complete FunctionFactory implementation. For more details: - http://docs.geotools.org/latest/userguide/tutorial/advanced/factory.html - http://docs.geotools.org/latest/userguide/tutorial/advanced/function.html Jody On 29/06/2012, at 10:39 PM, Trupti Pol wrote: > Hi, > > I am trying to develope a custom function "ColorMap" which can be used in > SLD to get the different style based on feature attributes. > > This function is mainly utilized to provide different draw color to each > feature based on the "ColorIndex" attribute. > > My Sample function is as follows > > public class ColorMapFunction extends FunctionExpressionImpl{ > > public ColorMapFunction(String name) { > super("ColorMap"); > } > > @Override > public int getArgCount() { > return 1; > } > > public Object evaluate(Object feature) { > String colorIndex; > > > try { > colorIndex = getExpression(0).evaluate(feature).toString(); > } catch (Exception e){ // probably a type error > throw new IllegalArgumentException( > "Filter Function problem for function ColorMap > argument #0 - expected type String"); > } > > return getColor(colorIndex); > } > > private String getColor(String colorTablePath, String colorIndex){ > // will provide different color based on colorIndex > } > } > > But when i try to use this function in my .sld file it gives me error as > below > > Unable to find function Colourmap >> java.lang.RuntimeException: Unable to find function Colourmap >> at >> org.geotools.filter.FunctionFinder.findFunction(FunctionFinder.java:103) >> at >> org.geotools.filter.FunctionFinder.findFunction(FunctionFinder.java:69) >> at >> org.geotools.filter.FilterFactoryImpl.function(FilterFactoryImpl.java:469) > > > Please let me know am i skipping something here..I am using geotools 2.6 M2 > version > > -- > View this message in context: > http://gis.19327.n5.nabble.com/Unable-to-find-custom-function-Colourmap-tp5714582.html > Sent from the uDig Developer mailing list archive at Nabble.com. > _______________________________________________ > User-friendly Desktop Internet GIS (uDig) > http://udig.refractions.net > http://lists.refractions.net/mailman/listinfo/udig-devel _______________________________________________ User-friendly Desktop Internet GIS (uDig) http://udig.refractions.net http://lists.refractions.net/mailman/listinfo/udig-devel
