org.jfree.data.time.Millisecond Maven / Gradle / Ivy
/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2005, 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.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* ----------------
* Millisecond.java
* ----------------
* (C) Copyright 2001-2005, by Object Refinery Limited.
*
* Original Author: David Gilbert (for Object Refinery Limited);
* Contributor(s): -;
*
* $Id: Millisecond.java,v 1.5.2.1 2005/10/25 21:35:24 mungady Exp $
*
* Changes
* -------
* 11-Oct-2001 : Version 1 (DG);
* 19-Dec-2001 : Added new constructors as suggested by Paul English (DG);
* 26-Feb-2002 : Added new getStart() and getEnd() methods (DG);
* 29-Mar-2002 : Fixed bug in getStart(), getEnd() and compareTo() methods (DG);
* 10-Sep-2002 : Added getSerialIndex() method (DG);
* 07-Oct-2002 : Fixed errors reported by Checkstyle (DG);
* 10-Jan-2003 : Changed base class and method names (DG);
* 13-Mar-2003 : Moved to com.jrefinery.data.time package and implemented
* Serializable (DG);
* 21-Oct-2003 : Added hashCode() method (DG);
*
*/
package org.jfree.data.time;
import java.io.Serializable;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;
/**
* Represents a millisecond. This class is immutable, which is a requirement
* for all {@link RegularTimePeriod} subclasses.
*/
public class Millisecond extends RegularTimePeriod implements Serializable {
/** For serialization. */
static final long serialVersionUID = -5316836467277638485L;
/** A constant for the first millisecond in a second. */
public static final int FIRST_MILLISECOND_IN_SECOND = 0;
/** A constant for the last millisecond in a second. */
public static final int LAST_MILLISECOND_IN_SECOND = 999;
/** The millisecond. */
private int millisecond;
/** The second. */
private Second second;
/**
* Constructs a millisecond based on the current system time.
*/
public Millisecond() {
this(new Date());
}
/**
* Constructs a millisecond.
*
* @param millisecond the millisecond (0-999).
* @param second the second.
*/
public Millisecond(int millisecond, Second second) {
this.millisecond = millisecond;
this.second = second;
}
/**
* Creates a new millisecond.
*
* @param millisecond the millisecond (0-999).
* @param second the second (0-59).
* @param minute the minute (0-59).
* @param hour the hour (0-23).
* @param day the day (1-31).
* @param month the month (1-12).
* @param year the year (1900-9999).
*/
public Millisecond(int millisecond, int second, int minute, int hour,
int day, int month, int year) {
this(millisecond, new Second(second, minute, hour, day, month, year));
}
/**
* Constructs a millisecond.
*
* @param time the time.
*/
public Millisecond(Date time) {
this(time, RegularTimePeriod.DEFAULT_TIME_ZONE);
}
/**
* Creates a millisecond.
*
* @param time the instant in time.
* @param zone the time zone.
*/
public Millisecond(Date time, TimeZone zone) {
this.second = new Second(time, zone);
Calendar calendar = Calendar.getInstance(zone);
calendar.setTime(time);
this.millisecond = calendar.get(Calendar.MILLISECOND);
}
/**
* Returns the second.
*
* @return The second.
*/
public Second getSecond() {
return this.second;
}
/**
* Returns the millisecond.
*
* @return The millisecond.
*/
public long getMillisecond() {
return this.millisecond;
}
/**
* Returns the millisecond preceding this one.
*
* @return The millisecond preceding this one.
*/
public RegularTimePeriod previous() {
RegularTimePeriod result = null;
if (this.millisecond != FIRST_MILLISECOND_IN_SECOND) {
result = new Millisecond(this.millisecond - 1, this.second);
}
else {
Second previous = (Second) this.second.previous();
if (previous != null) {
result = new Millisecond(LAST_MILLISECOND_IN_SECOND, previous);
}
}
return result;
}
/**
* Returns the millisecond following this one.
*
* @return The millisecond following this one.
*/
public RegularTimePeriod next() {
RegularTimePeriod result = null;
if (this.millisecond != LAST_MILLISECOND_IN_SECOND) {
result = new Millisecond(this.millisecond + 1, this.second);
}
else {
Second next = (Second) this.second.next();
if (next != null) {
result = new Millisecond(FIRST_MILLISECOND_IN_SECOND, next);
}
}
return result;
}
/**
* Returns a serial index number for the millisecond.
*
* @return The serial index number.
*/
public long getSerialIndex() {
return this.second.getSerialIndex() * 1000L + this.millisecond;
}
/**
* Tests the equality of this object against an arbitrary Object.
*
* This method will return true ONLY if the object is a Millisecond object
* representing the same millisecond as this instance.
*
* @param obj the object to compare
*
* @return true if milliseconds and seconds of this and object
* are the same.
*/
public boolean equals(Object obj) {
if (obj instanceof Millisecond) {
Millisecond m = (Millisecond) obj;
return ((this.millisecond == m.getMillisecond())
&& (this.second.equals(m.getSecond())));
}
else {
return false;
}
}
/**
* Returns a hash code for this object instance. The approach described by
* Joshua Bloch in "Effective Java" has been used here:
*
* http://developer.java.sun.com/developer/Books/effectivejava
* /Chapter3.pdf
*
* @return A hashcode.
*/
public int hashCode() {
int result = 17;
result = 37 * result + this.millisecond;
result = 37 * result + this.second.hashCode();
return result;
}
/**
* Returns an integer indicating the order of this Millisecond object
* relative to the specified object:
*
* negative == before, zero == same, positive == after.
*
* @param obj the object to compare
*
* @return negative == before, zero == same, positive == after.
*/
public int compareTo(Object obj) {
int result;
long difference;
// CASE 1 : Comparing to another Second object
// -------------------------------------------
if (obj instanceof Millisecond) {
Millisecond ms = (Millisecond) obj;
difference = getFirstMillisecond() - ms.getFirstMillisecond();
if (difference > 0) {
result = 1;
}
else {
if (difference < 0) {
result = -1;
}
else {
result = 0;
}
}
}
// CASE 2 : Comparing to another TimePeriod object
// -----------------------------------------------
else if (obj instanceof RegularTimePeriod) {
// more difficult case - evaluate later...
result = 0;
}
// CASE 3 : Comparing to a non-TimePeriod object
// ---------------------------------------------
else {
// consider time periods to be ordered after general objects
result = 1;
}
return result;
}
/**
* Returns the first millisecond of the time period.
*
* @return The first millisecond of the time period.
*/
public long getFirstMillisecond() {
return this.second.getFirstMillisecond() + this.millisecond;
}
/**
* Returns the first millisecond of the time period.
*
* @param calendar the calendar.
*
* @return The first millisecond of the time period.
*/
public long getFirstMillisecond(Calendar calendar) {
return this.second.getFirstMillisecond(calendar) + this.millisecond;
}
/**
* Returns the last millisecond of the time period.
*
* @return The last millisecond of the time period.
*/
public long getLastMillisecond() {
return this.second.getFirstMillisecond() + this.millisecond;
}
/**
* Returns the last millisecond of the time period.
*
* @param calendar the calendar.
*
* @return The last millisecond of the time period.
*/
public long getLastMillisecond(Calendar calendar) {
return this.second.getFirstMillisecond(calendar) + this.millisecond;
}
}