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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.]
*
* ----------
* Month.java
* ----------
* (C) Copyright 2001-present, by David Gilbert and Contributors.
*
* Original Author: David Gilbert;
* Contributor(s): Chris Boek;
*
*/
package org.jfree.data.time;
import java.io.Serializable;
import java.util.Calendar;
import java.util.Date;
import java.util.Locale;
import java.util.TimeZone;
import org.jfree.chart.date.MonthConstants;
import org.jfree.chart.date.SerialDate;
/**
* Represents a single month. This class is immutable, which is a requirement
* for all {@link RegularTimePeriod} subclasses.
*/
public class Month extends RegularTimePeriod implements Serializable {
/** For serialization. */
private static final long serialVersionUID = -5090216912548722570L;
/** The month (1-12). */
private int month;
/** The year in which the month falls. */
private int year;
/** The first millisecond. */
private long firstMillisecond;
/** The last millisecond. */
private long lastMillisecond;
/**
* Constructs a new Month, based on the current system time.
* The time zone and locale are determined by the calendar
* returned by {@link RegularTimePeriod#getCalendarInstance()}.
*/
public Month() {
this(new Date());
}
/**
* Constructs a new month instance.
* The time zone and locale are determined by the calendar
* returned by {@link RegularTimePeriod#getCalendarInstance()}.
*
* @param month the month (in the range 1 to 12).
* @param year the year.
*/
public Month(int month, int year) {
if ((month < 1) || (month > 12)) {
throw new IllegalArgumentException("Month outside valid range.");
}
this.month = month;
this.year = year;
peg(getCalendarInstance());
}
/**
* Constructs a new month instance.
* The time zone and locale are determined by the calendar
* returned by {@link RegularTimePeriod#getCalendarInstance()}.
*
* @param month the month (in the range 1 to 12).
* @param year the year.
*/
public Month(int month, Year year) {
if ((month < 1) || (month > 12)) {
throw new IllegalArgumentException("Month outside valid range.");
}
this.month = month;
this.year = year.getYear();
peg(getCalendarInstance());
}
/**
* Constructs a new {@code Month} instance, based on a date/time.
* The time zone and locale are determined by the calendar
* returned by {@link RegularTimePeriod#getCalendarInstance()}.
*
* @param time the date/time ({@code null} not permitted).
*
* @see #Month(Date, TimeZone, Locale)
*/
public Month(Date time) {
this(time, getCalendarInstance());
}
/**
* Creates a new {@code Month} instance, based on the specified time,
* zone and locale.
*
* @param time the current time.
* @param zone the time zone.
* @param locale the locale.
*/
public Month(Date time, TimeZone zone, Locale locale) {
Calendar calendar = Calendar.getInstance(zone, locale);
calendar.setTime(time);
this.month = calendar.get(Calendar.MONTH) + 1;
this.year = calendar.get(Calendar.YEAR);
peg(calendar);
}
/**
* Constructs a new instance, based on a particular date/time.
* The time zone and locale are determined by the {@code calendar}
* parameter.
*
* @param time the date/time ({@code null} not permitted).
* @param calendar the calendar to use for calculations ({@code null} not permitted).
*/
public Month(Date time, Calendar calendar) {
calendar.setTime(time);
this.month = calendar.get(Calendar.MONTH) + 1;
this.year = calendar.get(Calendar.YEAR);
peg(calendar);
}
/**
* Returns the year in which the month falls.
*
* @return The year in which the month falls (as a Year object).
*/
public Year getYear() {
return new Year(this.year);
}
/**
* Returns the year in which the month falls.
*
* @return The year in which the month falls (as an int).
*/
public int getYearValue() {
return this.year;
}
/**
* Returns the month. Note that 1=JAN, 2=FEB, ...
*
* @return The month.
*/
public int getMonth() {
return this.month;
}
/**
* Returns the first millisecond of the month. 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 month.
*
* @see #getLastMillisecond()
*/
@Override
public long getFirstMillisecond() {
return this.firstMillisecond;
}
/**
* Returns the last millisecond of the month. 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 month.
*
* @see #getFirstMillisecond()
*/
@Override
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} not permitted).
*/
@Override
public void peg(Calendar calendar) {
this.firstMillisecond = getFirstMillisecond(calendar);
this.lastMillisecond = getLastMillisecond(calendar);
}
/**
* Returns the month preceding this one. Note that the returned
* {@link Month} is "pegged" using the default calendar, obtained
* with {@link RegularTimePeriod#getCalendarInstance()}, irrespective of
* the time-zone used to peg of the current month (which is not recorded
* anywhere). See the {@link #peg(Calendar)} method.
*
* @return The month preceding this one.
*/
@Override
public RegularTimePeriod previous() {
Month result;
if (this.month != MonthConstants.JANUARY) {
result = new Month(this.month - 1, this.year);
}
else {
if (this.year > 1900) {
result = new Month(MonthConstants.DECEMBER, this.year - 1);
}
else {
result = null;
}
}
return result;
}
/**
* Returns the month following this one. Note that the returned
* {@link Month} is "pegged" using the default calendar, obtained
* with {@link RegularTimePeriod#getCalendarInstance()}, irrespective of
* the time-zone used to peg of the current month (which is not recorded
* anywhere). See the {@link #peg(Calendar)} method.
*
* @return The month following this one.
*/
@Override
public RegularTimePeriod next() {
Month result;
if (this.month != MonthConstants.DECEMBER) {
result = new Month(this.month + 1, this.year);
}
else {
if (this.year < 9999) {
result = new Month(MonthConstants.JANUARY, this.year + 1);
}
else {
result = null;
}
}
return result;
}
/**
* Returns a serial index number for the month.
*
* @return The serial index number.
*/
@Override
public long getSerialIndex() {
return this.year * 12L + this.month;
}
/**
* Returns a string representing the month (e.g. "January 2002").
*
* To do: look at internationalisation.
*
* @return A string representing the month.
*/
@Override
public String toString() {
return SerialDate.monthCodeToString(this.month) + " " + this.year;
}
/**
* Tests the equality of this Month object to an arbitrary object.
* Returns true if the target is a Month instance representing the same
* month as this object. In all other cases, returns false.
*
* @param obj the object ({@code null} permitted).
*
* @return {@code true} if month and year of this and object are the
* same.
*/
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof Month)) {
return false;
}
Month that = (Month) obj;
if (this.month != that.month) {
return false;
}
if (this.year != that.year) {
return false;
}
return true;
}
/**
* Returns a hash code for this object instance. The approach described by
* Joshua Bloch in "Effective Java" has been used here:
*
* {@code http://developer.java.sun.com/developer/Books/effectivejava
* /Chapter3.pdf}
*
* @return A hash code.
*/
@Override
public int hashCode() {
int result = 17;
result = 37 * result + this.month;
result = 37 * result + this.year;
return result;
}
/**
* Returns an integer indicating the order of this Month 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.
*/
@Override
public int compareTo(Object o1) {
int result;
// CASE 1 : Comparing to another Month object
// --------------------------------------------
if (o1 instanceof Month) {
Month m = (Month) o1;
result = this.year - m.getYearValue();
if (result == 0) {
result = this.month - m.getMonth();
}
}
// 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 the first millisecond of the month, evaluated using the supplied
* calendar (which determines the time zone).
*
* @param calendar the calendar ({@code null} not permitted).
*
* @return The first millisecond of the month.
*
* @throws NullPointerException if {@code calendar} is
* {@code null}.
*/
@Override
public long getFirstMillisecond(Calendar calendar) {
calendar.set(this.year, this.month - 1, 1, 0, 0, 0);
calendar.set(Calendar.MILLISECOND, 0);
return calendar.getTimeInMillis();
}
/**
* Returns the last millisecond of the month, evaluated using the supplied
* calendar (which determines the time zone).
*
* @param calendar the calendar ({@code null} not permitted).
*
* @return The last millisecond of the month.
*
* @throws NullPointerException if {@code calendar} is
* {@code null}.
*/
@Override
public long getLastMillisecond(Calendar calendar) {
int eom = SerialDate.lastDayOfMonth(this.month, this.year);
calendar.set(this.year, this.month - 1, eom, 23, 59, 59);
calendar.set(Calendar.MILLISECOND, 999);
return calendar.getTimeInMillis();
}
/**
* Parses the string argument as a month. This method is required to
* accept the format "YYYY-MM". It will also accept "MM-YYYY". Anything
* else, at the moment, is a bonus.
*
* @param s the string to parse ({@code null} permitted).
*
* @return {@code null} if the string is not parseable, the month
* otherwise.
*/
public static Month parseMonth(String s) {
Month result = null;
if (s == null) {
return result;
}
// trim whitespace from either end of the string
s = s.trim();
int i = Month.findSeparator(s);
String s1, s2;
boolean yearIsFirst;
// if there is no separator, we assume the first four characters
// are YYYY
if (i == -1) {
yearIsFirst = true;
s1 = s.substring(0, 5);
s2 = s.substring(5);
}
else {
s1 = s.substring(0, i).trim();
s2 = s.substring(i + 1).trim();
// now it is trickier to determine if the month or year is first
Year y1 = Month.evaluateAsYear(s1);
if (y1 == null) {
yearIsFirst = false;
}
else {
Year y2 = Month.evaluateAsYear(s2);
if (y2 == null) {
yearIsFirst = true;
}
else {
yearIsFirst = (s1.length() > s2.length());
}
}
}
Year year;
int month;
if (yearIsFirst) {
year = Month.evaluateAsYear(s1);
month = SerialDate.stringToMonthCode(s2);
}
else {
year = Month.evaluateAsYear(s2);
month = SerialDate.stringToMonthCode(s1);
}
if (month == -1) {
throw new TimePeriodFormatException("Can't evaluate the month.");
}
if (year == null) {
throw new TimePeriodFormatException("Can't evaluate the year.");
}
result = new Month(month, year);
return result;
}
/**
* Finds the first occurrence of '-', or if that character is not found,
* the first occurrence of ',', or the first occurrence of ' ' or '.'
*
* @param s the string to parse.
*
* @return The position of the separator character, or {@code -1} if
* none of the characters were found.
*/
private static int findSeparator(String s) {
int result = s.indexOf('-');
if (result == -1) {
result = s.indexOf(',');
}
if (result == -1) {
result = s.indexOf(' ');
}
if (result == -1) {
result = s.indexOf('.');
}
return result;
}
/**
* Creates a year from a string, or returns {@code null} (format
* exceptions suppressed).
*
* @param s the string to parse.
*
* @return {@code null} if the string is not parseable, the year
* otherwise.
*/
private static Year evaluateAsYear(String s) {
Year result = null;
try {
result = Year.parseYear(s);
}
catch (TimePeriodFormatException e) {
// suppress
}
return result;
}
}