-/* Copyright (C) 2000, 2001 Free Software Foundation
+/* Scrollbar.java -- AWT Scrollbar widget
+ Copyright (C) 1999, 2000, 2001, 2002 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. */
- This file is part of libjava.
-
-This software is copyrighted work licensed under the terms of the
-Libjava License. Please consult the file "LIBJAVA_LICENSE" for
-details. */
package java.awt;
-import java.awt.event.*;
+
import java.awt.peer.ScrollbarPeer;
import java.awt.peer.ComponentPeer;
+import java.awt.event.AdjustmentListener;
+import java.awt.event.AdjustmentEvent;
+
+/**
+ * This class implements a scrollbar widget.
+ *
+ * @author Aaron M. Renn (arenn@urbanophile.com)
+ * @author Tom Tromey <tromey@cygnus.com>
+ */
+public class Scrollbar extends Component implements Adjustable,
+ java.io.Serializable
+{
+
+// FIXME: Serialization readObject/writeObject
+
+/*
+ * Static Variables
+ */
+
+/**
+ * Constant indicating that a scrollbar is horizontal.
+ */
+public static final int HORIZONTAL = 0;
+
+/**
+ * Constant indicating that a scrollbar is vertical.
+ */
+public static final int VERTICAL = 1;
+
+// Serialization Constant
+private static final long serialVersionUID = 8451667562882310543L;
+
+/*************************************************************************/
+
+/**
+ * @serial The amount by which the value of the scrollbar is changed
+ * when incrementing in line mode.
+ */
+private int lineIncrement;
+
+/**
+ * @serial The amount by which the value of the scrollbar is changed
+ * when incrementing in page mode.
+ */
+private int pageIncrement;
+
+/**
+ * @serial The maximum value for this scrollbar
+ */
+private int maximum;
+
+/**
+ * @serial The minimum value for this scrollbar
+ */
+private int minimum;
+
/**
- * @author Tom Tromey <tromey@cygnus.com>
- * @date April 12, 2000
+ * @serial The orientation of this scrollbar, which will be either
+ * the <code>HORIZONTAL</code> or <code>VERTICAL</code> constant
+ * from this class.
+ */
+private int orientation;
+
+/**
+ * @serial The current value of this scrollbar.
+ */
+private int value;
+
+/**
+ * @serial The width of the scrollbar's thumb, which is relative
+ * to the minimum and maximum value of the scrollbar.
+ */
+private int visibleAmount;
+
+// List of AdjustmentListener's.
+private AdjustmentListener adjustment_listeners;
+
+/*************************************************************************/
+
+/*
+ * Constructors
*/
-public class Scrollbar extends Component implements Adjustable
-{
- public Scrollbar ()
- {
- this (VERTICAL, 0, 10, 0, 100);
- }
-
- public Scrollbar (int orientation)
- {
- this (orientation, 0, 10, 0, 100);
- }
-
- public Scrollbar (int orientation, int value, int visible,
- int minimum, int maximum)
- {
- if (orientation != HORIZONTAL && orientation != VERTICAL)
- throw new IllegalArgumentException ();
-
- if (maximum < minimum)
- maximum = minimum;
- if (value < minimum)
- value = minimum;
- if (value > maximum)
- value = maximum;
-
- this.orientation = orientation;
- this.value = value;
- this.visible = visible;
- this.minimum = minimum;
- this.maximum = maximum;
- this.unit = 1;
-
- this.block = 0; // FIXME
- }
-
- public void addNotify ()
- {
- if (peer == null)
- peer = getToolkit ().createScrollbar (this);
- super.addNotify ();
- }
-
- public int getOrientation ()
- {
- return orientation;
- }
-
- public void setOrientation (int orientation)
- {
- if (orientation != HORIZONTAL && orientation != VERTICAL)
- throw new IllegalArgumentException ();
- this.orientation = orientation;
- }
-
- public int getValue ()
- {
- return value;
- }
-
- public void setValue (int value)
- {
- setValues (value, visible, minimum, maximum);
- }
-
- public int getMinimum ()
- {
- return minimum;
- }
-
- public void setMinimum (int minimum)
- {
- setValues (value, visible, minimum, maximum);
- }
-
- public int getMaximum ()
- {
- return maximum;
- }
-
- public void setMaximum (int maximum)
- {
- setValues (value, visible, minimum, maximum);
- }
-
- public int getVisibleAmount ()
- {
- return visible;
- }
-
- public int getVisible ()
- {
- return visible;
- }
-
- public void setVisibleAmount (int visible)
- {
- setValues (value, visible, minimum, maximum);
- }
-
- public void setUnitIncrement (int v)
- {
- unit = v;
- if (peer != null)
- {
- ScrollbarPeer sp = (ScrollbarPeer) peer;
- sp.setLineIncrement (v);
- }
- }
-
- /** @deprecated */
- public void setLineIncrement (int v)
- {
- setUnitIncrement (v);
- }
-
- public int getUnitIncrement ()
- {
- return unit;
- }
-
- public int getLineIncrement ()
- {
- return unit;
- }
-
- public void setBlockIncrement (int v)
- {
- block = v;
- if (peer != null)
- {
- ScrollbarPeer sp = (ScrollbarPeer) peer;
- sp.setPageIncrement (v);
- }
- }
-
- public void setPageIncrement (int v)
- {
- setBlockIncrement (v);
- }
-
- public int getBlockIncrement ()
- {
- return block;
- }
-
- public int getPageIncrement ()
- {
- return block;
- }
-
- public synchronized void setValues (int value, int visible,
- int minimum, int maximum)
- {
- if (maximum < minimum)
- maximum = minimum;
- if (value < minimum)
- value = minimum;
- if (value > maximum)
- value = maximum;
-
- this.value = value;
- this.visible = visible;
- this.minimum = minimum;
- this.maximum = maximum;
-
- if (peer != null)
- {
- ScrollbarPeer sp = (ScrollbarPeer) peer;
- sp.setValues (value, visible, minimum, maximum);
- }
- }
-
- public void addAdjustmentListener (AdjustmentListener l)
- {
- listeners = AWTEventMulticaster.add (listeners, l);
- }
-
- public void removeAdjustmentListener (AdjustmentListener l)
- {
- listeners = AWTEventMulticaster.remove (listeners, l);
- }
-
- protected void processEvent (AWTEvent e)
- {
- if (e instanceof AdjustmentEvent)
- processAdjustmentEvent ((AdjustmentEvent) e);
- else
- super.processEvent (e);
- }
-
- protected void processAdjustmentEvent (AdjustmentEvent e)
- {
- if (listeners != null)
- listeners.adjustmentValueChanged (e);
- }
-
- protected String paramString ()
- {
- return ("Scrollbar["
- + ((orientation == VERTICAL) ? "VERTICAL" : "HORIZONTAL") + ","
- + value + ","
- + visible + ","
- + minimum + ","
- + maximum + ","
- + unit + ","
- + block + "]");
- }
-
- private AdjustmentListener listeners;
- private int orientation;
- private int value;
- private int visible;
- private int minimum;
- private int maximum;
- private int unit;
- private int block;
+/**
+ * Initializes a new instance of <code>Scrollbar</code> with a
+ * veritical orientation and default values for all other parameters.
+ */
+public
+Scrollbar()
+{
+ this(VERTICAL);
+}
+
+/*************************************************************************/
+
+/**
+ * Initializes a new instance of <code>Scrollbar</code> with the
+ * specified orientation and default values for all other parameters.
+ * The orientation must be either the constant <code>HORIZONTAL</code> or
+ * <code>VERTICAL</code> from this class. An incorrect value will throw
+ * an exception.
+ *
+ * @param orientation The orientation of this scrollbar.
+ *
+ * @exception IllegalArgumentException If the orientation value is not valid.
+ */
+public
+Scrollbar(int orientation) throws IllegalArgumentException
+{
+ this(orientation, 0, 10, 0, 100);
+}
+
+/*************************************************************************/
+
+/**
+ * Initializes a new instance of <code>Scrollbar</code> with the
+ * specified parameters. The orientation must be either the constant
+ * <code>HORIZONTAL</code> or <code>VERTICAL</code>. An incorrect value
+ * will throw an exception. Inconsistent values for other parameters
+ * are silently corrected to valid values.
+ *
+ * @param orientation The orientation of this scrollbar.
+ * @param value The initial value of the scrollbar.
+ * @param visibleAmount The width of the scrollbar thumb.
+ * @param minimum The minimum value of the scrollbar.
+ * @param maximum The maximum value of the scrollbar.
+ *
+ * @exception IllegalArgumentException If the orientation value is not valid.
+ */
+public
+Scrollbar(int orientation, int value, int visibleAmount, int minimum,
+ int maximum) throws IllegalArgumentException
+{
+ if ((orientation != HORIZONTAL) && (orientation != VERTICAL))
+ throw new IllegalArgumentException("Bad orientation value: "
+ + orientation);
+
+ this.orientation = orientation;
+
+ setValues(value, visibleAmount, minimum, maximum);
+
+ // Default is 1 according to online docs.
+ lineIncrement = 1;
+
+ pageIncrement = (maximum - minimum) / 5;
+ if (pageIncrement == 0)
+ pageIncrement = 1;
}
+
+/*************************************************************************/
+
+/*
+ * Instance Methods
+ */
+
+/**
+ * Returns the orientation constant for this object.
+ *
+ * @return The orientation constant for this object.
+ */
+public int
+getOrientation()
+{
+ return(orientation);
+}
+
+/*************************************************************************/
+
+/**
+ * Sets the orientation of this scrollbar to the specified value. This
+ * value must be either the constant <code>HORIZONTAL</code> or
+ * <code>VERTICAL</code> from this class or an exception will be thrown.
+ *
+ * @param orientation The new orientation value.
+ *
+ * @exception IllegalArgumentException If the orientation value is not valid.
+ */
+public void
+setOrientation(int orientation)
+{
+ if ((orientation != HORIZONTAL) && (orientation != VERTICAL))
+ throw new IllegalArgumentException("Bad orientation value: "
+ + orientation);
+
+ // FIXME: Communicate to peer? Or must this be called before peer creation?
+ this.orientation = orientation;
+}
+
+/*************************************************************************/
+
+/**
+ * Returns the current value for this scrollbar.
+ *
+ * @return The current value for this scrollbar.
+ */
+public int
+getValue()
+{
+ return(value);
+}
+
+/*************************************************************************/
+
+/**
+ * Sets the current value for this scrollbar to the specified value.
+ * If this is inconsistent with the minimum and maximum values for this
+ * scrollbar, the value is silently adjusted.
+ *
+ * @param value The new value for this scrollbar.
+ */
+public void
+setValue(int value)
+{
+ setValues(value, visibleAmount, minimum, maximum);
+}
+
+/*************************************************************************/
+
+/**
+ * Returns the maximum value for this scrollbar.
+ *
+ * @return The maximum value for this scrollbar.
+ */
+public int
+getMaximum()
+{
+ return(maximum);
+}
+
+/*************************************************************************/
+
+/**
+ * Sets the maximum value for this scrollbar to the specified value.
+ * If the value is less than the current minimum value, it is silent
+ * set to equal the minimum value.
+ *
+ * @param maximum The new maximum value for this scrollbar.
+ */
+public void
+setMaximum(int maximum)
+{
+ setValues(value, visibleAmount, minimum, maximum);
+}
+
+/*************************************************************************/
+
+/**
+ * Returns the minimum value for this scrollbar.
+ *
+ * @return The minimum value for this scrollbar.
+ */
+public int
+getMinimum()
+{
+ return(minimum);
+}
+
+/*************************************************************************/
+
+/**
+ * Sets the minimum value for this scrollbar to the specified value. If
+ * this is not consistent with the current value and maximum, it is
+ * silently adjusted to be consistent.
+ *
+ * @param minimum The new minimum value for this scrollbar.
+ */
+public void
+setMinimum(int minimum)
+{
+ setValues(value, visibleAmount, minimum, maximum);
+}
+
+/*************************************************************************/
+
+/**
+ * Returns the width of the scrollbar's thumb, in units relative to the
+ * maximum and minimum value of the scrollbar.
+ *
+ * @return The width of the scrollbar's thumb.
+ */
+public int
+getVisibleAmount()
+{
+ return(visibleAmount);
+}
+
+/*************************************************************************/
+
+/**
+ * Returns the width of the scrollbar's thumb, in units relative to the
+ * maximum and minimum value of the scrollbar.
+ *
+ * @return The width of the scrollbar's thumb.
+ *
+ * @deprecated This method is deprecated in favor of
+ * <code>getVisibleAmount()</code>.
+ */
+public int
+getVisible()
+{
+ return(getVisibleAmount());
+}
+
+/*************************************************************************/
+
+/**
+ * Sets the width of the scrollbar's thumb, in units relative to the
+ * maximum and minimum value of the scrollbar.
+ *
+ * @param visibileAmount The new visible amount value of the scrollbar.
+ */
+public void
+setVisibleAmount(int visibleAmount)
+{
+ setValues(value, visibleAmount, minimum, maximum);
+}
+
+/*************************************************************************/
+
+/**
+ * Sets the current value, visible amount, minimum, and maximum for this
+ * scrollbar. These values are adjusted to be internally consistent
+ * if necessary.
+ *
+ * @param value The new value for this scrollbar.
+ * @param visibleAmount The new visible amount for this scrollbar.
+ * @param minimum The new minimum value for this scrollbar.
+ * @param maximum The new maximum value for this scrollbar.
+ */
+public synchronized void
+setValues(int value, int visibleAmount, int minimum, int maximum)
+{
+ if (maximum < minimum)
+ maximum = minimum;
+
+ if (value < minimum)
+ value = minimum;
+
+ if (value > maximum)
+ value = maximum;
+
+ if (visibleAmount > value)
+ visibleAmount = value;
+
+ this.value = value;
+ this.visibleAmount = visibleAmount;
+ this.minimum = minimum;
+ this.maximum = maximum;
+
+ ScrollbarPeer sp = (ScrollbarPeer)getPeer();
+ if (sp != null)
+ sp.setValues(value, visibleAmount, minimum, maximum);
+
+ int range = maximum - minimum;
+ if (lineIncrement > range)
+ {
+ if (range == 0)
+ lineIncrement = 1;
+ else
+ lineIncrement = range;
+
+ if (sp != null)
+ sp.setLineIncrement(lineIncrement);
+ }
+
+ if (pageIncrement > range)
+ {
+ if (range == 0)
+ pageIncrement = 1;
+ else
+ pageIncrement = range;
+
+ if (sp != null)
+ sp.setPageIncrement(pageIncrement);
+ }
+}
+
+/*************************************************************************/
+
+/**
+ * Returns the value added or subtracted when the user activates the scrollbar
+ * scroll by a "unit" amount.
+ *
+ * @return The unit increment value.
+ */
+public int
+getUnitIncrement()
+{
+ return(lineIncrement);
+}
+
+/*************************************************************************/
+
+/**
+ * Returns the value added or subtracted when the user selects the scrollbar
+ * scroll by a "unit" amount control.
+ *
+ * @return The unit increment value.
+ *
+ * @deprecated This method is deprecated in favor of
+ * <code>getUnitIncrement()</code>.
+ */
+public int
+getLineIncrement()
+{
+ return(lineIncrement);
+}
+
+/*************************************************************************/
+
+/**
+ * Sets the value added or subtracted to the scrollbar value when the
+ * user selects the scroll by a "unit" amount control.
+ *
+ * @param unitIncrement The new unit increment amount.
+ */
+public synchronized void
+setUnitIncrement(int unitIncrement)
+{
+ if (unitIncrement < 0)
+ throw new IllegalArgumentException("Unit increment less than zero.");
+
+ int range = maximum - minimum;
+ if (unitIncrement > range)
+ {
+ if (range == 0)
+ unitIncrement = 1;
+ else
+ unitIncrement = range;
+ }
+
+ if (unitIncrement == lineIncrement)
+ return;
+
+ lineIncrement = unitIncrement;
+
+ ScrollbarPeer sp = (ScrollbarPeer)getPeer();
+ if (sp != null)
+ sp.setLineIncrement(lineIncrement);
+}
+
+/*************************************************************************/
+
+/**
+ * Sets the value added or subtracted to the scrollbar value when the
+ * user selects the scroll by a "unit" amount control.
+ *
+ * @param lineIncrement The new unit increment amount.
+ *
+ * @deprecated This method is deprecated in favor of
+ * <code>setUnitIncrement()</code>.
+ */
+public void
+setLineIncrement(int lineIncrement)
+{
+ setUnitIncrement(lineIncrement);
+}
+
+/*************************************************************************/
+
+/**
+ * Returns the value added or subtracted when the user activates the scrollbar
+ * scroll by a "block" amount.
+ *
+ * @return The block increment value.
+ */
+public int
+getBlockIncrement()
+{
+ return(pageIncrement);
+}
+
+/*************************************************************************/
+
+/**
+ * Returns the value added or subtracted when the user selects the scrollbar
+ * scroll by a "block" amount control.
+ *
+ * @return The block increment value.
+ *
+ * @deprecated This method is deprecated in favor of
+ * <code>getBlockIncrement()</code>.
+ */
+public int
+getPageIncrement()
+{
+ return(pageIncrement);
+}
+
+/*************************************************************************/
+
+/**
+ * Sets the value added or subtracted to the scrollbar value when the
+ * user selects the scroll by a "block" amount control.
+ *
+ * @param blockIncrement The new block increment amount.
+ */
+public synchronized void
+setBlockIncrement(int blockIncrement)
+{
+ if (blockIncrement < 0)
+ throw new IllegalArgumentException("Block increment less than zero.");
+
+ int range = maximum - minimum;
+ if (blockIncrement > range)
+ {
+ if (range == 0)
+ blockIncrement = 1;
+ else
+ blockIncrement = range;
+ }
+
+ if (blockIncrement == pageIncrement)
+ return;
+
+ pageIncrement = blockIncrement;
+
+ ScrollbarPeer sp = (ScrollbarPeer)getPeer();
+ if (sp != null)
+ sp.setPageIncrement(pageIncrement);
+}
+
+/*************************************************************************/
+
+/**
+ * Sets the value added or subtracted to the scrollbar value when the
+ * user selects the scroll by a "block" amount control.
+ *
+ * @param pageIncrement The new block increment amount.
+ *
+ * @deprecated This method is deprecated in favor of
+ * <code>setBlockIncrement()</code>.
+ */
+public void
+setPageIncrement(int pageIncrement)
+{
+ setBlockIncrement(pageIncrement);
+}
+
+/*************************************************************************/
+
+/**
+ * Notifies this object to create its native peer.
+ */
+public synchronized void
+addNotify()
+{
+ if (peer == null)
+ peer = getToolkit ().createScrollbar (this);
+ super.addNotify ();
+}
+
+/*************************************************************************/
+
+/**
+ * Adds a new adjustment listener to the list of registered listeners
+ * for this object.
+ *
+ * @param listener The listener to add.
+ */
+public synchronized void
+addAdjustmentListener(AdjustmentListener listener)
+{
+ adjustment_listeners = AWTEventMulticaster.add(adjustment_listeners, listener);
+ enableEvents(AWTEvent.ADJUSTMENT_EVENT_MASK);
+}
+
+/*************************************************************************/
+
+/**
+ * Removes the specified listener from the list of registered listeners
+ * for this object.
+ *
+ * @param listener The listener to remove.
+ */
+public synchronized void
+removeAdjustmentListener(AdjustmentListener listener)
+{
+ adjustment_listeners = AWTEventMulticaster.remove(adjustment_listeners,
+ listener);
+}
+
+/*************************************************************************/
+
+/**
+ * Processes events for this scrollbar. It does this by calling
+ * <code>processAdjustmentEvent()</code> if the event is an instance of
+ * <code>AdjustmentEvent</code>, otherwise it calls the superclass to
+ * process the event.
+ *
+ * @param event The event to process.
+ */
+protected void
+processEvent(AWTEvent event)
+{
+ if (event instanceof AdjustmentEvent)
+ processAdjustmentEvent((AdjustmentEvent)event);
+ else
+ super.processEvent(event);
+}
+
+/*************************************************************************/
+
+/**
+ * Processes adjustment events for this object by dispatching them to
+ * any registered listeners. Note that this method will only be called
+ * if adjustment events are enabled. This will happen automatically if
+ * any listeners are registered. Otherwise, it can be enabled by a
+ * call to <code>enableEvents()</code>.
+ *
+ * @param event The event to process.
+ */
+protected void
+processAdjustmentEvent(AdjustmentEvent event)
+{
+ if (adjustment_listeners != null)
+ adjustment_listeners.adjustmentValueChanged(event);
+}
+
+/*************************************************************************/
+
+/**
+ * Returns a debugging string for this object.
+ *
+ * @return A debugging string for this object.
+ */
+protected String
+paramString()
+{
+ return("value=" + getValue() + ",visibleAmount=" +
+ getVisibleAmount() + ",minimum=" + getMinimum()
+ + ",maximum=" + getMaximum()
+ + ",pageIncrement=" + pageIncrement
+ + ",lineIncrement=" + lineIncrement
+ + ",orientation=" + (orientation == HORIZONTAL
+ ? "HORIZONTAL" : "VERTICAL")
+ + super.paramString());
+}
+
+} // class Scrollbar
+
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