geopackage-sdk/src/main/java/mil/nga/geopackage/extension/style/FeatureTableStyles.java
public void setIcon(long featureId, GeometryType geometryType, IconRow icon) {
        featureStyleExtension.setIcon(tableName, featureId, geometryType, icon);
    }
public void setIcon(long featureId, GeometryType geometryType, IconRow icon) {
        featureStyleExtension.setIcon(tableName, featureId, geometryType, icon);
    }
Get the icon of the feature, searching in order: feature geometry type
icon, feature default icon, table geometry type icon, table default icon

@param featureId    feature id
@param geometryType geometry type
@param icon         icon row