/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2012, by Object Refinery Limited 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.]
*
* -----------------------
* TimeSeriesDataItem.java
* -----------------------
* (C) Copyright 2001-2012, by Object Refinery Limited.
*
* Original Author: David Gilbert (for Object Refinery Limited);
* Contributor(s): -;
*
* Changes
* -------
* 11-Oct-2001 : Version 1 (DG);
* 15-Nov-2001 : Updated Javadoc comments (DG);
* 29-Nov-2001 : Added cloning (DG);
* 24-Jun-2002 : Removed unnecessary import (DG);
* 07-Oct-2002 : Fixed errors reported by Checkstyle (DG);
* 13-Mar-2003 : Renamed TimeSeriesDataPair --> TimeSeriesDataItem, moved to
* com.jrefinery.data.time package, implemented Serializable (DG)
* ------------- JFREECHART 1.0.x ---------------------------------------------
* 09-Jun-2009 : Tidied up equals() (DG);
* 17-Jun-2012 : Removed JCommon dependencies (DG);
*
*/
package org.jfree.data.time;
import java.io.Serializable;
import org.jfree.chart.util.ObjectUtils;
/**
* Represents one data item in a time series.
* <P>
* The time period can be any of the following:
* <ul>
* <li>{@link Year}</li>
* <li>{@link Quarter}</li>
* <li>{@link Month}</li>
* <li>{@link Week}</li>
* <li>{@link Day}</li>
* <li>{@link Hour}</li>
* <li>{@link Minute}</li>
* <li>{@link Second}</li>
* <li>{@link Millisecond}</li>
* <li>{@link FixedMillisecond}</li>
* </ul>
*
* The time period is an immutable property of the data item. Data items will
* often be sorted within a list, and allowing the time period to be changed
* could destroy the sort order.
* <P>
* Implements the <code>Comparable</code> interface so that standard Java
* sorting can be used to keep the data items in order.
*
*/
public class TimeSeriesDataItem implements Cloneable, Comparable<TimeSeriesDataItem>, Serializable {
/** For serialization. */
private static final long serialVersionUID = -2235346966016401302L;
/** The time period. */
private RegularTimePeriod period;
/** The value associated with the time period. */
private Number value;
/**
* Constructs a new data item that associates a value with a time period.
*
* @param period the time period (<code>null</code> not permitted).
* @param value the value (<code>null</code> permitted).
*/
public TimeSeriesDataItem(RegularTimePeriod period, Number value) {
if (period == null) {
throw new IllegalArgumentException("Null 'period' argument.");
}
this.period = period;
this.value = value;
}
/**
* Constructs a new data item that associates a value with a time period.
*
* @param period the time period (<code>null</code> not permitted).
* @param value the value associated with the time period.
*/
public TimeSeriesDataItem(RegularTimePeriod period, double value) {
this(period, new Double(value));
}
/**
* Returns the time period.
*
* @return The time period (never <code>null</code>).
*/
public RegularTimePeriod getPeriod() {
return this.period;
}
/**
* Returns the value.
*
* @return The value (<code>null</code> possible).
*
* @see #setValue(java.lang.Number)
*/
public Number getValue() {
return this.value;
}
/**
* Sets the value for this data item.
*
* @param value the value (<code>null</code> permitted).
*
* @see #getValue()
*/
public void setValue(Number value) {
this.value = value;
}
/**
* Tests this object for equality with an arbitrary object.
*
* @param obj the other object (<code>null</code> permitted).
*
* @return A boolean.
*/
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (!(obj instanceof TimeSeriesDataItem)) {
return false;
}
TimeSeriesDataItem that = (TimeSeriesDataItem) obj;
if (!ObjectUtils.equal(this.period, that.period)) {
return false;
}
if (!ObjectUtils.equal(this.value, that.value)) {
return false;
}
return true;
}
/**
* Returns a hash code.
*
* @return A hash code.
*/
@Override
public int hashCode() {
int result;
result = (this.period != null ? this.period.hashCode() : 0);
result = 29 * result + (this.value != null ? this.value.hashCode() : 0);
return result;
}
/**
* Returns an integer indicating the order of this data pair object
* relative to another object.
* <P>
* For the order we consider only the timing:
* negative == before, zero == same, positive == after.
*
* @param o1 The object being compared to.
*
* @return An integer indicating the order of the data item object
* relative to another object.
*/
@Override
public int compareTo(TimeSeriesDataItem o1) {
return getPeriod().compareTo(o1.getPeriod());
}
/**
* Clones the data item. Note: there is no need to clone the period or
* value since they are immutable classes.
*
* @return A clone of the data item.
*/
@Override
public Object clone() {
Object clone = null;
try {
clone = super.clone();
}
catch (CloneNotSupportedException e) { // won't get here...
e.printStackTrace();
}
return clone;
}
}