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diff --git a/java/awt/image/LookupTable.java b/java/awt/image/LookupTable.java
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+/* LookupTable.java -- Java class for a pixel translation table.
+   Copyright (C) 2004 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package java.awt.image;
+
+/**
+ * LookupTable represents translation arrays for pixel values.  It wraps one
+ * or more data arrays for each layer (or component) in an image, such as
+ * Alpha, R, G, and B.  When doing translation, the offset is subtracted from
+ * the pixel values to allow a subset of an array to be used.
+ *
+ * @see ByteLookupTable
+ * @see ShortLookupTable
+ *
+ * @author <a href="mailto:jlquinn@optonline.net">Jerry Quinn</a>
+ * @version 1.0
+ */
+public abstract class LookupTable
+{
+  // Not protected since that's part of the public API.
+  int offset;
+  int numComponents;
+
+  /**
+   * Creates a new <code>LookupTable</code> instance.
+   *
+   * If numComponents is 1, the same translation table is used for all pixel
+   * components.
+   * 
+   * @param offset Offset to be subtracted.
+   * @param numComponents Number of image components.
+   * @exception IllegalArgumentException if offset < 0 or numComponents < 1.
+   */
+  protected LookupTable(int offset, int numComponents)
+    throws IllegalArgumentException
+  {
+    if (offset < 0 || numComponents < 1)
+      throw new IllegalArgumentException();
+    this.offset = offset;
+    this.numComponents = numComponents;
+  }
+
+  /** Return the number of components. */
+  public int getNumComponents()
+  {
+    return numComponents;
+  }
+
+  /** Return the offset. */
+  public int getOffset()
+  {
+    return offset;
+  }
+
+  
+  /**
+   * Return translated values for a pixel.
+   *
+   * For each value in the pixel src, use the value minus offset as an index
+   * in the component array and copy the value there to the output for the
+   * component.  If dest is null, the output is a new array, otherwise the
+   * translated values are written to dest.  Dest can be the same array as
+   * src.
+   *
+   * For example, if the pixel src is [2, 4, 3], and offset is 1, the output
+   * is [comp1[1], comp2[3], comp3[2]], where comp1, comp2, and comp3 are the
+   * translation arrays.
+   *
+   * @param src Component values of a pixel.
+   * @param dest Destination array for values, or null.
+   * @return Translated values for the pixel.
+   */
+  public abstract int[] lookupPixel(int[] src, int[] dest);
+}