/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2007, 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.]
*
* ---------
* Year.java
* ---------
* (C) Copyright 2001-2007, by Object Refinery Limited.
*
* Original Author: David Gilbert (for Object Refinery Limited);
* Contributor(s): -;
*
* Changes
* -------
* 11-Oct-2001 : Version 1 (DG);
* 14-Nov-2001 : Override for toString() method (DG);
* 19-Dec-2001 : Added a new constructor as suggested by Paul English (DG);
* 29-Jan-2002 : Worked on parseYear() method (DG);
* 14-Feb-2002 : Fixed bug in Year(Date) constructor (DG);
* 26-Feb-2002 : Changed getStart(), getMiddle() and getEnd() methods to
* evaluate with reference to a particular time zone (DG);
* 19-Mar-2002 : Changed API for TimePeriod classes (DG);
* 10-Sep-2002 : Added getSerialIndex() method (DG);
* 04-Oct-2002 : Fixed errors reported by Checkstyle (DG);
* 10-Jan-2003 : Changed base class and method names (DG);
* 05-Mar-2003 : Fixed bug in getFirstMillisecond() picked up in JUnit
* tests (DG);
* 13-Mar-2003 : Moved to com.jrefinery.data.time package, and implemented
* Serializable (DG);
* 21-Oct-2003 : Added hashCode() method (DG);
* ------------- JFREECHART 1.0.x ---------------------------------------------
* 05-Oct-2006 : Updated API docs (DG);
* 06-Oct-2006 : Refactored to cache first and last millisecond values (DG);
*
*/
package org.jfree.data.time;
import java.io.Serializable;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;
import org.jfree.date.SerialDate;
/**
* Represents a year in the range 1900 to 9999. This class is immutable, which
* is a requirement for all {@link RegularTimePeriod} subclasses.
*/
public class Year extends RegularTimePeriod implements Serializable {
/** For serialization. */
private static final long serialVersionUID = -7659990929736074836L;
/** The year. */
private short year;
/** The first millisecond. */
private long firstMillisecond;
/** The last millisecond. */
private long lastMillisecond;
/**
* Creates a new <code>Year</code>, based on the current system date/time.
*/
public Year() {
this(new Date());
}
/**
* Creates a time period representing a single year.
*
* @param year the year.
*/
public Year(int year) {
if ((year < SerialDate.MINIMUM_YEAR_SUPPORTED)
|| (year > SerialDate.MAXIMUM_YEAR_SUPPORTED)) {
throw new IllegalArgumentException(
"Year constructor: year (" + year + ") outside valid range.");
}
this.year = (short) year;
peg(Calendar.getInstance());
}
/**
* Creates a new <code>Year</code>, based on a particular instant in time,
* using the default time zone.
*
* @param time the time (<code>null</code> not permitted).
*/
public Year(Date time) {
this(time, RegularTimePeriod.DEFAULT_TIME_ZONE);
}
/**
* Constructs a year, based on a particular instant in time and a time zone.
*
* @param time the time.
* @param zone the time zone.
*/
public Year(Date time, TimeZone zone) {
Calendar calendar = Calendar.getInstance(zone);
calendar.setTime(time);
this.year = (short) calendar.get(Calendar.YEAR);
peg(calendar);
}
/**
* Returns the year.
*
* @return The year.
*/
public int getYear() {
return this.year;
}
/**
* Returns the first millisecond of the year. This will be determined
* relative to the time zone specified in the constructor, or in the
* calendar instance passed in the most recent call to the
* {@link #peg(Calendar)} method.
*
* @return The first millisecond of the year.
*
* @see #getLastMillisecond()
*/
public long getFirstMillisecond() {
return this.firstMillisecond;
}
/**
* Returns the last millisecond of the year. This will be
* determined relative to the time zone specified in the constructor, or
* in the calendar instance passed in the most recent call to the
* {@link #peg(Calendar)} method.
*
* @return The last millisecond of the year.
*
* @see #getFirstMillisecond()
*/
public long getLastMillisecond() {
return this.lastMillisecond;
}
/**
* Recalculates the start date/time and end date/time for this time period
* relative to the supplied calendar (which incorporates a time zone).
*
* @param calendar the calendar (<code>null</code> not permitted).
*
* @since 1.0.3
*/
public void peg(Calendar calendar) {
this.firstMillisecond = getFirstMillisecond(calendar);
this.lastMillisecond = getLastMillisecond(calendar);
}
/**
* Returns the year preceding this one.
*
* @return The year preceding this one (or <code>null</code> if the
* current year is 1900).
*/
public RegularTimePeriod previous() {
if (this.year > SerialDate.MINIMUM_YEAR_SUPPORTED) {
return new Year(this.year - 1);
}
else {
return null;
}
}
/**
* Returns the year following this one.
*
* @return The year following this one (or <code>null</code> if the current
* year is 9999).
*/
public RegularTimePeriod next() {
if (this.year < SerialDate.MAXIMUM_YEAR_SUPPORTED) {
return new Year(this.year + 1);
}
else {
return null;
}
}
/**
* Returns a serial index number for the year.
* <P>
* The implementation simply returns the year number (e.g. 2002).
*
* @return The serial index number.
*/
public long getSerialIndex() {
return this.year;
}
/**
* Returns the first millisecond of the year, evaluated using the supplied
* calendar (which determines the time zone).
*
* @param calendar the calendar (<code>null</code> not permitted).
*
* @return The first millisecond of the year.
*
* @throws NullPointerException if <code>calendar</code> is
* <code>null</code>.
*/
public long getFirstMillisecond(Calendar calendar) {
calendar.set(this.year, Calendar.JANUARY, 1, 0, 0, 0);
calendar.set(Calendar.MILLISECOND, 0);
// in the following line, we'd rather call calendar.getTimeInMillis()
// to avoid object creation, but that isn't supported in Java 1.3.1
return calendar.getTime().getTime();
}
/**
* Returns the last millisecond of the year, evaluated using the supplied
* calendar (which determines the time zone).
*
* @param calendar the calendar (<code>null</code> not permitted).
*
* @return The last millisecond of the year.
*
* @throws NullPointerException if <code>calendar</code> is
* <code>null</code>.
*/
public long getLastMillisecond(Calendar calendar) {
calendar.set(this.year, Calendar.DECEMBER, 31, 23, 59, 59);
calendar.set(Calendar.MILLISECOND, 999);
// in the following line, we'd rather call calendar.getTimeInMillis()
// to avoid object creation, but that isn't supported in Java 1.3.1
return calendar.getTime().getTime();
}
/**
* Tests the equality of this <code>Year</code> object to an arbitrary
* object. Returns <code>true</code> if the target is a <code>Year</code>
* instance representing the same year as this object. In all other cases,
* returns <code>false</code>.
*
* @param object the object (<code>null</code> permitted).
*
* @return <code>true</code> if the year of this and the object are the
* same.
*/
public boolean equals(Object object) {
if (object != null) {
if (object instanceof Year) {
Year target = (Year) object;
return (this.year == target.getYear());
}
else {
return false;
}
}
else {
return false;
}
}
/**
* Returns a hash code for this object instance. The approach described by
* Joshua Bloch in "Effective Java" has been used here:
* <p>
* <code>http://developer.java.sun.com/developer/Books/effectivejava
* /Chapter3.pdf</code>
*
* @return A hash code.
*/
public int hashCode() {
int result = 17;
int c = this.year;
result = 37 * result + c;
return result;
}
/**
* Returns an integer indicating the order of this <code>Year</code> object
* relative to the specified object:
*
* negative == before, zero == same, positive == after.
*
* @param o1 the object to compare.
*
* @return negative == before, zero == same, positive == after.
*/
public int compareTo(Object o1) {
int result;
// CASE 1 : Comparing to another Year object
// -----------------------------------------
if (o1 instanceof Year) {
Year y = (Year) o1;
result = this.year - y.getYear();
}
// CASE 2 : Comparing to another TimePeriod object
// -----------------------------------------------
else if (o1 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 a string representing the year..
*
* @return A string representing the year.
*/
public String toString() {
return Integer.toString(this.year);
}
/**
* Parses the string argument as a year.
* <P>
* The string format is YYYY.
*
* @param s a string representing the year.
*
* @return <code>null</code> if the string is not parseable, the year
* otherwise.
*/
public static Year parseYear(String s) {
// parse the string...
int y;
try {
y = Integer.parseInt(s.trim());
}
catch (NumberFormatException e) {
throw new TimePeriodFormatException("Cannot parse string.");
}
// create the year...
try {
return new Year(y);
}
catch (IllegalArgumentException e) {
throw new TimePeriodFormatException("Year outside valid range.");
}
}
}
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