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/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-present, by David Gilbert and Contributors.
*
* Project Info: http://www.jfree.org/jfreechart/index.html
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
* Other names may be trademarks of their respective owners.]
*
* -----------------------
* IntervalXYDelegate.java
* -----------------------
* (C) Copyright 2004-present, by Andreas Schroeder and Contributors.
*
* Original Author: Andreas Schroeder;
* Contributor(s): David Gilbert;
*
*/
package org.jfree.data.xy;
import java.io.Serializable;
import org.jfree.chart.HashUtils;
import org.jfree.chart.util.Args;
import org.jfree.chart.util.PublicCloneable;
import org.jfree.data.DomainInfo;
import org.jfree.data.Range;
import org.jfree.data.RangeInfo;
import org.jfree.data.general.DatasetChangeEvent;
import org.jfree.data.general.DatasetChangeListener;
import org.jfree.data.general.DatasetUtils;
/**
* A delegate that handles the specification or automatic calculation of the
* interval surrounding the x-values in a dataset. This is used to extend
* a regular {@link XYDataset} to support the {@link IntervalXYDataset}
* interface.
*
* The decorator pattern was not used because of the several possibly
* implemented interfaces of the decorated instance (e.g.
* {@link TableXYDataset}, {@link RangeInfo}, {@link DomainInfo} etc.).
*
* The width can be set manually or calculated automatically. The switch
* autoWidth allows to determine which behavior is used. The auto width
* calculation tries to find the smallest gap between two x-values in the
* dataset. If there is only one item in the series, the auto width
* calculation fails and falls back on the manually set interval width (which
* is itself defaulted to 1.0).
*/
public class IntervalXYDelegate implements DatasetChangeListener,
DomainInfo, Serializable, Cloneable, PublicCloneable {
/** For serialization. */
private static final long serialVersionUID = -685166711639592857L;
/**
* The dataset to enhance.
*/
private XYDataset dataset;
/**
* A flag to indicate whether the width should be calculated automatically.
*/
private boolean autoWidth;
/**
* A value between 0.0 and 1.0 that indicates the position of the x-value
* within the interval.
*/
private double intervalPositionFactor;
/**
* The fixed interval width (defaults to 1.0).
*/
private double fixedIntervalWidth;
/**
* The automatically calculated interval width.
*/
private double autoIntervalWidth;
/**
* Creates a new delegate that.
*
* @param dataset the underlying dataset ({@code null} not permitted).
*/
public IntervalXYDelegate(XYDataset dataset) {
this(dataset, true);
}
/**
* Creates a new delegate for the specified dataset.
*
* @param dataset the underlying dataset ({@code null} not permitted).
* @param autoWidth a flag that controls whether the interval width is
* calculated automatically.
*/
public IntervalXYDelegate(XYDataset dataset, boolean autoWidth) {
Args.nullNotPermitted(dataset, "dataset");
this.dataset = dataset;
this.autoWidth = autoWidth;
this.intervalPositionFactor = 0.5;
this.autoIntervalWidth = Double.POSITIVE_INFINITY;
this.fixedIntervalWidth = 1.0;
}
/**
* Returns {@code true} if the interval width is automatically
* calculated, and {@code false} otherwise.
*
* @return A boolean.
*/
public boolean isAutoWidth() {
return this.autoWidth;
}
/**
* Sets the flag that indicates whether the interval width is automatically
* calculated. If the flag is set to {@code true}, the interval is
* recalculated.
*
* Note: recalculating the interval amounts to changing the data values
* represented by the dataset. The calling dataset must fire an
* appropriate {@link DatasetChangeEvent}.
*
* @param b a boolean.
*/
public void setAutoWidth(boolean b) {
this.autoWidth = b;
if (b) {
this.autoIntervalWidth = recalculateInterval();
}
}
/**
* Returns the interval position factor.
*
* @return The interval position factor.
*/
public double getIntervalPositionFactor() {
return this.intervalPositionFactor;
}
/**
* Sets the interval position factor. This controls how the interval is
* aligned to the x-value. For a value of 0.5, the interval is aligned
* with the x-value in the center. For a value of 0.0, the interval is
* aligned with the x-value at the lower end of the interval, and for a
* value of 1.0, the interval is aligned with the x-value at the upper
* end of the interval.
*
* Note that changing the interval position factor amounts to changing the
* data values represented by the dataset. Therefore, the dataset that is
* using this delegate is responsible for generating the
* appropriate {@link DatasetChangeEvent}.
*
* @param d the new interval position factor (in the range
* {@code 0.0} to {@code 1.0} inclusive).
*/
public void setIntervalPositionFactor(double d) {
if (d < 0.0 || 1.0 < d) {
throw new IllegalArgumentException(
"Argument 'd' outside valid range.");
}
this.intervalPositionFactor = d;
}
/**
* Returns the fixed interval width.
*
* @return The fixed interval width.
*/
public double getFixedIntervalWidth() {
return this.fixedIntervalWidth;
}
/**
* Sets the fixed interval width and, as a side effect, sets the
* {@code autoWidth} flag to {@code false}.
*
* Note that changing the interval width amounts to changing the data
* values represented by the dataset. Therefore, the dataset
* that is using this delegate is responsible for generating the
* appropriate {@link DatasetChangeEvent}.
*
* @param w the width (negative values not permitted).
*/
public void setFixedIntervalWidth(double w) {
if (w < 0.0) {
throw new IllegalArgumentException("Negative 'w' argument.");
}
this.fixedIntervalWidth = w;
this.autoWidth = false;
}
/**
* Returns the interval width. This method will return either the
* auto calculated interval width or the manually specified interval
* width, depending on the {@link #isAutoWidth()} result.
*
* @return The interval width to use.
*/
public double getIntervalWidth() {
if (isAutoWidth() && !Double.isInfinite(this.autoIntervalWidth)) {
// everything is fine: autoWidth is on, and an autoIntervalWidth
// was set.
return this.autoIntervalWidth;
}
else {
// either autoWidth is off or autoIntervalWidth was not set.
return this.fixedIntervalWidth;
}
}
/**
* Returns the start value of the x-interval for an item within a series.
*
* @param series the series index.
* @param item the item index.
*
* @return The start value of the x-interval (possibly {@code null}).
*
* @see #getStartXValue(int, int)
*/
public Number getStartX(int series, int item) {
Number startX = null;
Number x = this.dataset.getX(series, item);
if (x != null) {
startX = x.doubleValue() - (getIntervalPositionFactor() * getIntervalWidth());
}
return startX;
}
/**
* Returns the start value of the x-interval for an item within a series.
*
* @param series the series index.
* @param item the item index.
*
* @return The start value of the x-interval.
*
* @see #getStartX(int, int)
*/
public double getStartXValue(int series, int item) {
return this.dataset.getXValue(series, item)
- getIntervalPositionFactor() * getIntervalWidth();
}
/**
* Returns the end value of the x-interval for an item within a series.
*
* @param series the series index.
* @param item the item index.
*
* @return The end value of the x-interval (possibly {@code null}).
*
* @see #getEndXValue(int, int)
*/
public Number getEndX(int series, int item) {
Number endX = null;
Number x = this.dataset.getX(series, item);
if (x != null) {
endX = x.doubleValue() + ((1.0 - getIntervalPositionFactor()) * getIntervalWidth());
}
return endX;
}
/**
* Returns the end value of the x-interval for an item within a series.
*
* @param series the series index.
* @param item the item index.
*
* @return The end value of the x-interval.
*
* @see #getEndX(int, int)
*/
public double getEndXValue(int series, int item) {
return this.dataset.getXValue(series, item)
+ (1.0 - getIntervalPositionFactor()) * getIntervalWidth();
}
/**
* Returns the minimum x-value in the dataset.
*
* @param includeInterval a flag that determines whether or not the
* x-interval is taken into account.
*
* @return The minimum value.
*/
@Override
public double getDomainLowerBound(boolean includeInterval) {
double result = Double.NaN;
Range r = getDomainBounds(includeInterval);
if (r != null) {
result = r.getLowerBound();
}
return result;
}
/**
* Returns the maximum x-value in the dataset.
*
* @param includeInterval a flag that determines whether or not the
* x-interval is taken into account.
*
* @return The maximum value.
*/
@Override
public double getDomainUpperBound(boolean includeInterval) {
double result = Double.NaN;
Range r = getDomainBounds(includeInterval);
if (r != null) {
result = r.getUpperBound();
}
return result;
}
/**
* Returns the range of the values in the dataset's domain, including
* or excluding the interval around each x-value as specified.
*
* @param includeInterval a flag that determines whether or not the
* x-interval should be taken into account.
*
* @return The range.
*/
@Override
public Range getDomainBounds(boolean includeInterval) {
// first get the range without the interval, then expand it for the
// interval width
Range range = DatasetUtils.findDomainBounds(this.dataset, false);
if (includeInterval && range != null) {
double lowerAdj = getIntervalWidth() * getIntervalPositionFactor();
double upperAdj = getIntervalWidth() - lowerAdj;
range = new Range(range.getLowerBound() - lowerAdj,
range.getUpperBound() + upperAdj);
}
return range;
}
/**
* Handles events from the dataset by recalculating the interval if
* necessary.
*
* @param e the event.
*/
@Override
public void datasetChanged(DatasetChangeEvent e) {
// TODO: by coding the event with some information about what changed
// in the dataset, we could make the recalculation of the interval
// more efficient in some cases (for instance, if the change is
// just an update to a y-value, then the x-interval doesn't need
// updating)...
if (this.autoWidth) {
this.autoIntervalWidth = recalculateInterval();
}
}
/**
* Recalculate the minimum width "from scratch".
*
* @return The minimum width.
*/
private double recalculateInterval() {
double result = Double.POSITIVE_INFINITY;
int seriesCount = this.dataset.getSeriesCount();
for (int series = 0; series < seriesCount; series++) {
result = Math.min(result, calculateIntervalForSeries(series));
}
return result;
}
/**
* Calculates the interval width for a given series.
*
* @param series the series index.
*
* @return The interval width.
*/
private double calculateIntervalForSeries(int series) {
double result = Double.POSITIVE_INFINITY;
int itemCount = this.dataset.getItemCount(series);
if (itemCount > 1) {
double prev = this.dataset.getXValue(series, 0);
for (int item = 1; item < itemCount; item++) {
double x = this.dataset.getXValue(series, item);
result = Math.min(result, x - prev);
prev = x;
}
}
return result;
}
/**
* Tests the delegate for equality with an arbitrary object. The
* equality test considers two delegates to be equal if they would
* calculate the same intervals for any given dataset (for this reason, the
* dataset itself is NOT included in the equality test, because it is just
* a reference back to the current 'owner' of the delegate).
*
* @param obj the object ({@code null} permitted).
*
* @return A boolean.
*/
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof IntervalXYDelegate)) {
return false;
}
IntervalXYDelegate that = (IntervalXYDelegate) obj;
if (this.autoWidth != that.autoWidth) {
return false;
}
if (this.intervalPositionFactor != that.intervalPositionFactor) {
return false;
}
if (this.fixedIntervalWidth != that.fixedIntervalWidth) {
return false;
}
return true;
}
/**
* @return A clone of this delegate.
*
* @throws CloneNotSupportedException if the object cannot be cloned.
*/
@Override
public Object clone() throws CloneNotSupportedException {
return super.clone();
}
/**
* Returns a hash code for this instance.
*
* @return A hash code.
*/
@Override
public int hashCode() {
int hash = 5;
hash = HashUtils.hashCode(hash, this.autoWidth);
hash = HashUtils.hashCode(hash, this.intervalPositionFactor);
hash = HashUtils.hashCode(hash, this.fixedIntervalWidth);
return hash;
}
}