From f4b4a695f425c1c60c375fe3af1b3b5e34499e2e Mon Sep 17 00:00:00 2001
From: Sebastian Graca <sgraca@ispik.pl>
Date: Sat, 22 Sep 2012 14:32:23 +0200
Subject: [PATCH] add parameter for multiple input transparent colors

---
 .../coverage/grid/io/AbstractGridFormat.java       |  6 ++++++
 .../src/main/java/org/geotools/util/Utilities.java | 14 ++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/modules/library/coverage/src/main/java/org/geotools/coverage/grid/io/AbstractGridFormat.java b/modules/library/coverage/src/main/java/org/geotools/coverage/grid/io/AbstractGridFormat.java
index d8e45de90ae..ad774d92332 100644
--- a/modules/library/coverage/src/main/java/org/geotools/coverage/grid/io/AbstractGridFormat.java
+++ b/modules/library/coverage/src/main/java/org/geotools/coverage/grid/io/AbstractGridFormat.java
@@ -19,6 +19,7 @@
 import java.awt.Color;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import javax.imageio.ImageWriteParam;
 
@@ -31,6 +32,7 @@
 import org.geotools.parameter.DefaultParameterDescriptor;
 import org.geotools.referencing.crs.DefaultEngineeringCRS;
 import org.geotools.referencing.factory.epsg.CartesianAuthorityFactory;
+import org.geotools.util.Utilities;
 import org.opengis.coverage.grid.Format;
 import org.opengis.coverage.grid.GridCoverageReader;
 import org.opengis.coverage.grid.GridCoverageWriter;
@@ -188,6 +190,10 @@ public abstract class AbstractGridFormat implements Format {
     public static final ParameterDescriptor<Color> INPUT_TRANSPARENT_COLOR = new DefaultParameterDescriptor<Color>(
                 "InputTransparentColor", Color.class, null, null);
     
+    /** Control the transparency of the input coverages (allows to set multiple transparent colors). */
+    public static final ParameterDescriptor<Set<Color>> INPUT_TRANSPARENT_COLORS = new DefaultParameterDescriptor<Set<Color>>(
+                "InputTransparentColors", Utilities.<Class<Set<Color>>>cast(Set.class), null, null);
+    
     /** Control the background color to be used where the input was transparent */
     public static final ParameterDescriptor<Color> BACKGROUND_COLOR = new DefaultParameterDescriptor<Color>(
                 "BackgroundColor", Color.class, null, null);
diff --git a/modules/library/metadata/src/main/java/org/geotools/util/Utilities.java b/modules/library/metadata/src/main/java/org/geotools/util/Utilities.java
index f00d9ffa241..6e09c888d76 100644
--- a/modules/library/metadata/src/main/java/org/geotools/util/Utilities.java
+++ b/modules/library/metadata/src/main/java/org/geotools/util/Utilities.java
@@ -148,6 +148,20 @@ protected Object readResolve() throws ObjectStreamException {
      */
     private Utilities() {
     }
+    
+    /**
+     * Casts passed value to inferred type T.
+     * 
+     * Can be used to eliminate usge of {@code @SuppressWarnings("unchecked")} in code.
+     * 
+     * @param obj an object to be cast to type T.
+     *          
+     * @return the object cast to type T. 
+     */
+    @SuppressWarnings("unchecked")
+    public static <T> T cast(Object obj) {
+        return (T)obj;
+    }
 
     /**
      * Returns {@code true} if the given booleans are equals. This overloaded flavor is provided