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diff --git a/libjava/classpath/javax/swing/ViewportLayout.java b/libjava/classpath/javax/swing/ViewportLayout.java
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+/* ViewportLayout.java --
+   Copyright (C) 2002, 2004, 2006 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., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 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 javax.swing;
+
+import java.awt.Component;
+import java.awt.Container;
+import java.awt.Dimension;
+import java.awt.LayoutManager;
+import java.awt.Point;
+import java.awt.Rectangle;
+import java.io.Serializable;
+
+/**
+ * The default layout for {@link JViewport}. The viewport makes its view the
+ * same size as itself, but not smaller than its minimum size.
+ *
+ * If the port extends extends into space <em>past</em> the edge of the view,
+ * this layout manager moves the port up or to the left, in view space, by the
+ * amount of empty space (keep the lower and right edges lined up).
+ *
+ * @author  Andrew Selkirk
+ * @author  Graydon Hoare
+ * @author  Audrius Meskauskas (audriusa@Bioinformatics.org)
+ */
+public class ViewportLayout implements LayoutManager, Serializable
+{
+  private static final long serialVersionUID = -788225906076097229L;
+
+  public ViewportLayout()
+  {
+    // Nothing to do here.
+  }
+
+  /**
+   * The method is not used with this manager.
+   */
+  public void addLayoutComponent(String name, Component c)
+  {
+    // Nothing to do here.
+  }
+
+  /**
+   * The method is not used with this manager.
+   */
+  public void removeLayoutComponent(Component c)
+  {
+    // Nothing to do here.
+  }
+
+  /**
+   * Get the preferred layout size. If the view implements
+   * {@link Scrollable}, this method returns
+   * {@link Scrollable#getPreferredScrollableViewportSize}.
+   * Otherwise, it returns {@link Component#getPreferredSize()}.
+   *
+   * @return the preferred layout size, as described about.
+   */
+  public Dimension preferredLayoutSize(Container parent)
+  {
+    JViewport vp = (JViewport)parent;
+    Component view = vp.getView();
+    if (view != null)
+      {
+        if (view instanceof Scrollable)
+          return ((Scrollable)view).getPreferredScrollableViewportSize();
+        return view.getPreferredSize();
+      }
+    else
+      return new Dimension();
+  }
+
+  /**
+   * Get the minimum layout size. Normally this method returns the value,
+   * returned by the view method {@link Component#getMinimumSize()}.
+   *
+   * If the view is not set, the zero size is returned.
+   *
+   * @param parent the viewport
+   * @return the minimum layout size.
+   */
+  public Dimension minimumLayoutSize(Container parent)
+  {
+    // These values have been determined by the Mauve test for this method.
+    return new Dimension(4, 4);
+  }
+
+  /**
+   * Layout the view and viewport to respect the following rules. These are not
+   * precisely the rules described in sun's javadocs, but they are the rules
+   * which sun's swing implementation follows, if you watch its behavior:
+   * <ol>
+   * <li>If the port is smaller than the view, leave the view at its current
+   * size.</li>
+   * <li>If the view is smaller than the port, the view is top aligned.</li>
+   * <li>If the view tracks the port size, the view position is always zero and
+   * the size equal to the viewport size</li>
+   * <li>In {@link JViewport#setViewSize(Dimension)}, the view size is never
+   * set smaller that its minimum size.</li>
+   * </ol>
+   *
+   * @see JViewport#getViewSize
+   * @see JViewport#setViewSize
+   * @see JViewport#getViewPosition
+   * @see JViewport#setViewPosition
+   */
+  public void layoutContainer(Container parent)
+  {
+    // The way to interpret this function is basically to ignore the names
+    // of methods it calls, and focus on the variable names here. getViewRect
+    // doesn't, for example, return the view; it returns the port bounds in
+    // view space. Likwise setViewPosition doesn't reposition the view; it
+    // positions the port, in view coordinates.
+
+    JViewport port = (JViewport) parent;
+    Component view = port.getView();
+
+    if (view == null)
+      return;
+
+    // These dimensions and positions are in *view space*. Do not mix
+    // variables in here from port space (eg. parent.getBounds()). This
+    // function should be entirely in view space, because the methods on
+    // the viewport require inputs in view space.
+
+    Rectangle portBounds = port.getViewRect();
+    Dimension viewPref = new Dimension(view.getPreferredSize());
+
+    Point portLowerRight = new Point(portBounds.x + portBounds.width,
+                                     portBounds.y + portBounds.height);
+
+    // vertical implementation of the above rules
+    if (view instanceof Scrollable)
+      {
+        Scrollable sView = (Scrollable) view;
+
+        // If the view size matches viewport size, the port offset can
+        // only be zero.
+        if (sView.getScrollableTracksViewportWidth())
+          {
+            viewPref.width = portBounds.width;
+            portBounds.x = 0;
+          }
+        if (sView.getScrollableTracksViewportHeight())
+          {
+            viewPref.height = portBounds.height;
+            portBounds.y = 0;
+          }
+      }
+
+     if (viewPref.width < portBounds.width)
+       viewPref.width = portBounds.width;
+     if (viewPref.height < portBounds.height)
+       viewPref.height = portBounds.height;
+
+    // If the view is larger than the port, the port is top and right
+    // aligned.
+    if (portLowerRight.x > viewPref.width)
+      portBounds.x = 0;
+
+    if (portLowerRight.y > viewPref.height)
+      portBounds.y = 0;
+
+    port.setViewSize(viewPref);
+    port.setViewPosition(portBounds.getLocation());
+  }
+
+}