/*
* Copyright (c) 2000, 2008, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
package sun.jvm.hotspot.ui;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import java.math.*;
import java.util.*;
/** A JScrollBar which uses BigIntegers as the representation for the
minimum, maximum, unit increment, etc. Interaction with the
buttons and track is accurate to unit and block increments;
however, if the scale of the scrollbar (defined by
getMaximumHP().subtract(getMinimumHP())) is very large, each
interaction with the thumb will necessarily cause extremely large
motion of the value. */
public class HighPrecisionJScrollBar extends JScrollBar {
private BigInteger valueHP;
private BigInteger visibleHP;
private BigInteger minimumHP;
private BigInteger maximumHP;
private BigInteger unitIncrementHP;
private BigInteger blockIncrementHP;
private BigDecimal scaleFactor;
private BigInteger rangeHP;
// The underlying scrollbar runs a range from 0..BIG_RANGE-1
private static final int BIG_RANGE = 10000;
// Do we need to scale HP values up/down to fit in 0..BIG_RANGE-1?
private boolean down;
private java.util.List changeListeners = new ArrayList();
// Number of digits after decimal point to use when scaling between
// high and low precision
private static final int SCALE = 20;
// This is a hack to allow us to differentiate between clicks on the
// arrow and track since we can't get useful information from
// JScrollBars' AdjustmentListener (bug in design of BasicUI
// classes; FIXME: file RFE.)
private static final int UNIT_INCREMENT = 1;
private static final int BLOCK_INCREMENT = 2;
private static final int MINIMUM = 0;
private static final int MAXIMUM = 65536;
private boolean updating = false;
private int lastValueSeen = -1;
public HighPrecisionJScrollBar() {
super();
initialize();
installListener();
}
public HighPrecisionJScrollBar(int orientation) {
super(orientation);
initialize();
installListener();
}
/** value, minimum and maximum should be positive */
public HighPrecisionJScrollBar(int orientation, BigInteger value, BigInteger minimum, BigInteger maximum) {
super(orientation);
initialize(value, minimum, maximum);
installListener();
}
public BigInteger getValueHP() {
return valueHP;
}
/** NOTE: the real value will always be set to be (value mod
unitIncrement) == 0, subtracting off the mod of the passed value
if necessary. */
public void setValueHP(BigInteger value) {
if (value.compareTo(getMaximumHP()) > 0) {
value = getMaximumHP();
} else if (value.compareTo(getMinimumHP()) < 0) {
value = getMinimumHP();
}
valueHP = value.subtract(value.mod(unitIncrementHP));
int lpValue = toUnderlyingRange(this.valueHP);
if (getValueHP().add(getVisibleAmountHP()).compareTo(getMaximumHP()) >= 0 ) {
lpValue = BIG_RANGE - getVisibleAmount();
}
lastValueSeen = lpValue;
setValue(lpValue);
fireStateChanged();
}
public BigInteger getMinimumHP() {
return minimumHP;
}
public void setMinimumHP(BigInteger minimum) {
setRange(minimum, maximumHP);
updateScrollBarValues();
}
public BigInteger getMaximumHP() {
return maximumHP;
}
public void setMaximumHP(BigInteger maximum) {
setRange(minimumHP, maximum);
updateScrollBarValues();
}
public BigInteger getVisibleAmountHP() {
return visibleHP;
}
public void setVisibleAmountHP(BigInteger visibleAmount) {
this.visibleHP = visibleAmount;
// int lpVisAmt = toUnderlyingRange(visibleAmount);
// Make certain that visibleAmount value that are full range come out looking like full range
int lpVisAmt;
if (visibleAmount.compareTo(rangeHP) < 0) {
lpVisAmt = scaleToUnderlying(visibleAmount);
if (lpVisAmt == 0) {
lpVisAmt = 1;
}
setVisible(true);
} else {
lpVisAmt = BIG_RANGE;
setVisible(false);
}
setVisibleAmount(lpVisAmt);
}
public BigInteger getBlockIncrementHP() {
return blockIncrementHP;
}
public void setBlockIncrementHP(BigInteger blockIncrement) {
this.blockIncrementHP = blockIncrement;
// NOTE we do not forward this to the underlying scrollBar because of
// the earlier mentioned hack.
}
public BigInteger getUnitIncrementHP() {
return unitIncrementHP;
}
public void setUnitIncrementHP(BigInteger unitIncrement) {
this.unitIncrementHP = unitIncrement;
// NOTE we do not forward this to the underlying scrollBar because of
// the earlier mentioned hack.
}
public void addChangeListener(ChangeListener l) {
changeListeners.add(l);
}
public void removeChangeListener(ChangeListener l) {
changeListeners.remove(l);
}
//----------------------------------------------------------------------
// Programmatic access to scrollbar functionality
// (Causes change events to be sent)
public void scrollUpOrLeft() {
if (updating) return;
beginUpdate();
setValueHP(getValueHP().subtract(getUnitIncrementHP()));
endUpdate();
}
public void scrollDownOrRight() {
if (updating) return;
beginUpdate();
setValueHP(getValueHP().add(getUnitIncrementHP()));
endUpdate();
}
public void pageUpOrLeft() {
if (updating) return;
beginUpdate();
setValueHP(getValueHP().subtract(getBlockIncrementHP()));
endUpdate();
}
public void pageDownOrRight() {
if (updating) return;
beginUpdate();
setValueHP(getValueHP().add(getBlockIncrementHP()));
endUpdate();
}
//----------------------------------------------------------------------
// Internals only below this point
//
private void beginUpdate() {
updating = true;
}
private void endUpdate() {
updating = false;
}
private void initialize(BigInteger value, BigInteger minimum, BigInteger maximum) {
// Initialize the underlying scrollbar to the standard range values
// The increments are important and are how we differentiate arrow from track events
setMinimum(0);
setMaximum(BIG_RANGE - 1);
setValue(0);
setVisibleAmount(1);
setUnitIncrement(UNIT_INCREMENT);
setBlockIncrement(BLOCK_INCREMENT);
setUnitIncrementHP(new BigInteger(Integer.toString(getUnitIncrement())));
setBlockIncrementHP(new BigInteger(Integer.toString(getBlockIncrement())));
// Must set range and value first (it sets min/max)
setRange(minimum, maximum);
setVisibleAmountHP(new BigInteger(Integer.toString(getVisibleAmount())));
setValueHP(value);
}
private void initialize() {
BigInteger min = new BigInteger(Integer.toString(getMinimum()));
BigInteger max = new BigInteger(Integer.toString(getMaximum()));
initialize(min, min, max);
}
private void setRange(BigInteger minimum, BigInteger maximum) {
if (minimum.compareTo(maximum) > 0 ) {
throw new RuntimeException("Bad scrollbar range " + minimum + " > " + maximum);
}
minimumHP = minimum;
maximumHP = maximum;
rangeHP = maximum.subtract(minimum).add(BigInteger.ONE);
BigInteger range2 = new BigInteger(Integer.toString(BIG_RANGE));
if (rangeHP.compareTo(range2) >= 0 ) {
down = true;
scaleFactor = new BigDecimal(rangeHP, SCALE).divide(new BigDecimal(range2, SCALE), BigDecimal.ROUND_DOWN).max(new BigDecimal(BigInteger.ONE));
} else {
down = false;
scaleFactor = new BigDecimal(range2, SCALE).divide(new BigDecimal(rangeHP, SCALE), BigDecimal.ROUND_DOWN).max(new BigDecimal(BigInteger.ONE));
}
// FIXME: should put in original scaling algorithm (shifting by
// number of bits) as alternative when scale between low and high
// precision is very large
}
// A range update is complete. Rescale our computed values and
// inform the underlying scrollBar as needed.
private void updateScrollBarValues() {
setValueHP(getValueHP());
setVisibleAmountHP(getVisibleAmountHP());
setBlockIncrementHP(getBlockIncrementHP());
setUnitIncrementHP(getUnitIncrementHP());
}
private BigDecimal getScaleFactor() {
return scaleFactor;
}
// Value scaling routines
private BigInteger scaleToHP(int i) {
BigDecimal ib = new BigDecimal(Integer.toString(i));
if (down) return ib.multiply(getScaleFactor()).toBigInteger();
else return ib.divide(getScaleFactor(), BigDecimal.ROUND_DOWN).toBigInteger();
}
private int scaleToUnderlying(BigInteger i) {
BigDecimal d = new BigDecimal(i);
if (down) return d.divide(getScaleFactor(), BigDecimal.ROUND_DOWN).intValue();
else return d.multiply(getScaleFactor()).intValue();
}
// Range scaling routines
private BigInteger toHPRange(int i) {
return scaleToHP(i).add(minimumHP);
// return ib.shiftLeft(Math.max(2, maximumHP.bitLength() - 33));
}
private int toUnderlyingRange(BigInteger i) {
return scaleToUnderlying(i.subtract(minimumHP));
// return i.shiftRight(Math.max(2, maximumHP.bitLength() - 33)).intValue();
}
private void installListener() {
super.addAdjustmentListener(new AdjustmentListener() {
public void adjustmentValueChanged(AdjustmentEvent e) {
if (updating) {
return;
}
beginUpdate();
switch (e.getAdjustmentType()) {
case AdjustmentEvent.TRACK:
int val = e.getValue();
int diff = val - lastValueSeen;
int absDiff = Math.abs(diff);
// System.err.println("diff: " + diff + " absDiff: " + absDiff);
if (absDiff == UNIT_INCREMENT) {
if (diff > 0) {
// System.err.println("case 1");
setValueHP(getValueHP().add(getUnitIncrementHP()));
} else {
// System.err.println("case 2");
setValueHP(getValueHP().subtract(getUnitIncrementHP()));
}
} else if (absDiff == BLOCK_INCREMENT) {
if (diff > 0) {
// System.err.println("case 3");
setValueHP(getValueHP().add(getBlockIncrementHP()));
} else {
// System.err.println("case 4");
setValueHP(getValueHP().subtract(getBlockIncrementHP()));
}
} else {
// System.err.println("case 5");
// FIXME: seem to be getting spurious update events,
// with diff = 0, upon mouse down/up on the track
if (absDiff != 0) {
// Convert low-precision value to high precision
// (note we lose the low bits)
BigInteger i = null;
if (e.getValue() == getMinimum()) {
i = getMinimumHP();
} else if (e.getValue() >= getMaximum() - 1) {
i = getMaximumHP();
} else {
i = toHPRange(e.getValue());
}
setValueHP(i);
}
}
break;
default:
// Should not reach here, but leaving it a no-op in case
// we later get the other events (should revisit code in
// that case)
break;
}
endUpdate();
}
});
}
private void fireStateChanged() {
ChangeEvent e = null;
for (Iterator iter = changeListeners.iterator(); iter.hasNext(); ) {
ChangeListener l = (ChangeListener) iter.next();
if (e == null) {
e = new ChangeEvent(this);
}
l.stateChanged(e);
}
}
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setSize(300, 300);
// 32-bit version
/*
HighPrecisionJScrollBar hpsb =
new HighPrecisionJScrollBar(
JScrollBar.VERTICAL,
new BigInteger(1, new byte[] {
(byte) 0x80, (byte) 0x00, (byte) 0x00, (byte) 0x00}),
new BigInteger(1, new byte[] {
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00}),
new BigInteger(1, new byte[] {
(byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF}));
hpsb.setUnitIncrementHP(new BigInteger(1, new byte[] {
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x01}));
hpsb.setBlockIncrementHP(new BigInteger(1, new byte[] {
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x10}));
*/
// 64-bit version
HighPrecisionJScrollBar hpsb =
new HighPrecisionJScrollBar(
JScrollBar.VERTICAL,
new BigInteger(1, new byte[] {
(byte) 0x80, (byte) 0x00, (byte) 0x00, (byte) 0x00,
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00}),
new BigInteger(1, new byte[] {
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00}),
new BigInteger(1, new byte[] {
(byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF,
(byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF}));
hpsb.setUnitIncrementHP(new BigInteger(1, new byte[] {
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x01}));
hpsb.setBlockIncrementHP(new BigInteger(1, new byte[] {
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x10}));
hpsb.addChangeListener(new ChangeListener() {
public void stateChanged(ChangeEvent e) {
HighPrecisionJScrollBar h = (HighPrecisionJScrollBar) e.getSource();
System.out.println("New value = 0x" + h.getValueHP().toString(16));
}
});
frame.getContentPane().add(hpsb);
frame.setVisible(true);
}
}