2 files changed, 45 insertions, 13 deletions
diff --git a/java/awt/AlphaComposite.java b/java/awt/AlphaComposite.java
index addd1e713..a668fdae6 100644
--- a/java/awt/AlphaComposite.java
+++ b/java/awt/AlphaComposite.java
@@ -158,18 +158,53 @@ public final class AlphaComposite implements Composite
     return new AlphaCompositeContext(this, srcColorModel, dstColorModel);
   }
 
+  /**
+   * Return an <code>AlphaComposite</code> similar to <code>this</code>,
+   * that uses the specified rule. If <code>rule</code> is the same as
+   * <code>this.rule</code>, then <code>this</code> is returned.
+   * 
+   * @since 1.6
+   */
+  public AlphaComposite derive(int rule)
+  {
+    if (this.rule == rule)
+      return this;
+    else
+      return AlphaComposite.getInstance(rule, this.getAlpha());
+  }
+  
+  /**
+   * Return an <code>AlphaComposite</code> similar to <code>this</code>,
+   * that uses the specified <code>alpha</code>.
+   * 
+   * If <code>alph</code> is the same as <code>this.alpha</code>,
+   * then <code>this</code> is returned.
+   * 
+   * @since 1.6
+   */
+  public AlphaComposite derive(float alpha)
+  {
+      if (this.getAlpha() == alpha)
+        return this;
+      else
+        return AlphaComposite.getInstance(this.getRule(), alpha);
+  }
+  
   public float getAlpha()
   {
     return alpha;
   }
+  
   public int getRule()
   {
     return rule;
   }
+  
   public int hashCode()
   {
     return 31 * Float.floatToIntBits(alpha) + rule;
   }
+  
   public boolean equals(Object o)
   {
     if (! (o instanceof AlphaComposite))
diff --git a/java/awt/image/WritableRaster.java b/java/awt/image/WritableRaster.java
index bf8db140c..02789a3d1 100644
--- a/java/awt/image/WritableRaster.java
+++ b/java/awt/image/WritableRaster.java
@@ -111,13 +111,8 @@ public class WritableRaster extends Raster
   public WritableRaster createWritableTranslatedChild(int childMinX,
                                                       int childMinY)
   {
-    // This mirrors the code from the super class
-    int tcx = sampleModelTranslateX - minX + childMinX;
-    int tcy = sampleModelTranslateY - minY + childMinY;
-    
-    return new WritableRaster(sampleModel, dataBuffer,
-        new Rectangle(childMinX, childMinY, width, height), 
-        new Point(tcx, tcy), this);
+    return createWritableChild(minX, minY, width, height,
+                               childMinX, childMinY, null);
   }
 
   /**
@@ -143,12 +138,14 @@ public class WritableRaster extends Raster
     SampleModel sm = (bandList == null) ?
       sampleModel :
       sampleModel.createSubsetSampleModel(bandList);
-    
-    return new WritableRaster(sm, dataBuffer,
-        new Rectangle(childMinX, childMinY, w, h),
-        new Point(sampleModelTranslateX + childMinX - parentX,
-                  sampleModelTranslateY + childMinY - parentY),
-        this);
+
+    return new WritableRaster(sm, getDataBuffer(),
+                              new Rectangle(childMinX, childMinY, w, h),
+                              new Point(sampleModelTranslateX + childMinX -
+                                          parentX,
+                                        sampleModelTranslateY + childMinY -
+                                          parentY),
+                              this);
   }
   
   public Raster createChild(int parentX, int parentY, int width,