[Geotools-gt2-users] How to add an attribute from a shapefile as a label to text symbolizer?

[Niranjan k <nir...@gm...>]

Hi,

I am working on a project using GT2.2.1. I am totally new to this
environment, so please excuse my naive doubts!

I am trying to display polygons, given the co-ordinates as a shapefile,
which works just fine. But, now I want to also display a name within each
polygon.

The name to be displayed is actually present as an attribute(unique for each
polygon) in the original shapefile. I tried using createTextSymbolizer(),the
StyleFactory method, to do this, but it only allows me to set individual
Expressions as a label, and if I pass the attribute name, nothing appears on
the map.

How do i display the polygon name along with each polygon when it gets
displayed? I created two rules for that feature style, one
PolygonSymbolizer, and one TextSymbolizer, and also added both to the same
feature style. But even then, only the polygons get displayed, and not the
names.

Here is the code I used:

        StyleBuilder sb = new StyleBuilder();
        StyleFactory sf = StyleFactoryFinder.createStyleFactory();

        PolygonSymbolizer ps = sf.createPolygonSymbolizer();
        Fill fill1 = sf.createFill(ff.createLiteralExpression("#00FF00"));
        Stroke stroke = sf.createStroke(
                ff.createLiteralExpression("#FF0000"),
                ff.createLiteralExpression(2));
        ps.setFill(fill1);
        ps.setStroke(stroke);

        org.geotools.styling.Font font = sb.createFont(new Font("Serif",
Font.PLAIN, 8));
            org.geotools.styling.Font font1[] = new
org.geotools.styling.Font[1];
        font1[0]= font;
        Fill fill2 = sf.createFill(ff.createLiteralExpression("#000000"));
        TextSymbolizer ts = sf.createTextSymbolizer();
        ts.setFill(fill2);
        ts.setLabel(ff.createLiteralExpression(attrs[1].getName()));
        ts.setFonts(font1);

            Fill fill3= sf.createFill(ff.createLiteralExpression
("#ffffff"));
        Halo halo= sf.createHalo(fill3, ff.createLiteralExpression("1"));
        ts.setHalo(halo);

        Rule rule = sf.createRule();
        rule.setSymbolizers( new Symbolizer[]{ ps });

        Rule rulets = sf.createRule();
        rulets.setSymbolizers( new Symbolizer[]{ ts });

        FeatureTypeStyle type = sf.createFeatureTypeStyle();
        type.setFeatureTypeName(temp[0]);
        type.addRule(rule);

        FeatureTypeStyle typets = sf.createFeatureTypeStyle();
        typets.setFeatureTypeName(temp[0]);
        typets.addRule(rulets);

        Style style = sf.createStyle();
        style.addFeatureTypeStyle(type);
        style.addFeatureTypeStyle(typets);

Is this code correct?

Any help will be appreciated!

Thanks in advance,

Niranjan Kumar
M.S. Candidate
Department of Computer Science,
Iowa State University, Ames, IA