--- a/gnv-artifacts/src/main/java/de/intevation/gnv/raster/Filter.java	Tue Apr 06 13:07:11 2010 +0000
+++ b/gnv-artifacts/src/main/java/de/intevation/gnv/raster/Filter.java	Tue Apr 06 16:53:43 2010 +0000
@@ -3,18 +3,36 @@
 import org.w3c.dom.Element;
 
 /**
+ * Interface to model transformations of rasters.
  * @author <a href="mailto:sascha.teichmann@intevation.de">Sascha L. Teichmann</a>
  */
 public interface Filter
 {
+    /**
+     *  Allows the creation of filters parameterized from XML elements.
+     */
     public interface Factory {
 
+        /**
+         * Setup the factory with a given XML element.
+         * @param element
+         */
         void init(Element element);
 
+        /**
+         * Created a new Filter with this factory.
+         * @return The new created Filter.
+         */
         Filter create();
 
     } // interface Factory
 
+    /**
+     * Apply this filter to a given raster. The original raster is
+     * unmodified and a new raster is created.
+     * @param raster The original raster.
+     * @return The new raster.
+     */
     Raster filter(Raster raster);
 }
 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :