Source code

001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
006 *
007 * Project Info:  http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it 
010 * under the terms of the GNU Lesser General Public License as published by 
011 * the Free Software Foundation; either version 2.1 of the License, or 
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but 
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
022 * USA.  
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
025 * in the United States and other countries.]
026 *
027 * ------------
028 * Quarter.java
029 * ------------
030 * (C) Copyright 2001-2007, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * Changes
036 * -------
037 * 11-Oct-2001 : Version 1 (DG);
038 * 18-Dec-2001 : Changed order of parameters in constructor (DG);
039 * 19-Dec-2001 : Added a new constructor as suggested by Paul English (DG);
040 * 29-Jan-2002 : Added a new method parseQuarter(String) (DG);
041 * 14-Feb-2002 : Fixed bug in Quarter(Date) constructor (DG);
042 * 26-Feb-2002 : Changed getStart(), getMiddle() and getEnd() methods to 
043 *               evaluate with reference to a particular time zone (DG);
044 * 19-Mar-2002 : Changed API for TimePeriod classes (DG);
045 * 24-Jun-2002 : Removed main method (just test code) (DG);
046 * 10-Sep-2002 : Added getSerialIndex() method (DG);
047 * 07-Oct-2002 : Fixed errors reported by Checkstyle (DG);
048 * 10-Jan-2003 : Changed base class and method names (DG);
049 * 13-Mar-2003 : Moved to com.jrefinery.data.time package, and implemented 
050 *               Serializable (DG);
051 * 21-Oct-2003 : Added hashCode() method (DG);
052 * 10-Dec-2005 : Fixed argument checking bug (1377239) in constructor (DG);
053 * ------------- JFREECHART 1.0.x ---------------------------------------------
054 * 05-Oct-2006 : Updated API docs (DG);
055 * 06-Oct-2006 : Refactored to cache first and last millisecond values (DG);
056 *
057 */
058
059package org.jfree.data.time;
060
061import java.io.Serializable;
062import java.util.Calendar;
063import java.util.Date;
064import java.util.TimeZone;
065
066import org.jfree.date.MonthConstants;
067import org.jfree.date.SerialDate;
068
069/**
070 * Defines a quarter (in a given year).  The range supported is Q1 1900 to 
071 * Q4 9999.  This class is immutable, which is a requirement for all 
072 * {@link RegularTimePeriod} subclasses.
073 */
074public class Quarter extends RegularTimePeriod implements Serializable {
075
076    /** For serialization. */
077    private static final long serialVersionUID = 3810061714380888671L;
078    
079    /** Constant for quarter 1. */
080    public static final int FIRST_QUARTER = 1;
081
082    /** Constant for quarter 4. */
083    public static final int LAST_QUARTER = 4;
084
085    /** The first month in each quarter. */
086    public static final int[] FIRST_MONTH_IN_QUARTER = {
087        0, MonthConstants.JANUARY, MonthConstants.APRIL, MonthConstants.JULY, 
088        MonthConstants.OCTOBER
089    };
090
091    /** The last month in each quarter. */
092    public static final int[] LAST_MONTH_IN_QUARTER = {
093        0, MonthConstants.MARCH, MonthConstants.JUNE, MonthConstants.SEPTEMBER, 
094        MonthConstants.DECEMBER
095    };
096
097    /** The year in which the quarter falls. */
098    private short year;
099
100    /** The quarter (1-4). */
101    private byte quarter;
102
103    /** The first millisecond. */
104    private long firstMillisecond;
105    
106    /** The last millisecond. */
107    private long lastMillisecond;
108
109    /**
110     * Constructs a new Quarter, based on the current system date/time.
111     */
112    public Quarter() {
113        this(new Date());
114    }
115
116    /**
117     * Constructs a new quarter.
118     *
119     * @param year  the year (1900 to 9999).
120     * @param quarter  the quarter (1 to 4).
121     */
122    public Quarter(int quarter, int year) {
123        if ((quarter < FIRST_QUARTER) || (quarter > LAST_QUARTER)) {
124            throw new IllegalArgumentException("Quarter outside valid range.");
125        }
126        this.year = (short) year;
127        this.quarter = (byte) quarter;
128        peg(Calendar.getInstance());
129    }
130
131    /**
132     * Constructs a new quarter.
133     *
134     * @param quarter  the quarter (1 to 4).
135     * @param year  the year (1900 to 9999).
136     */
137    public Quarter(int quarter, Year year) {
138        if ((quarter < FIRST_QUARTER) || (quarter > LAST_QUARTER)) {
139            throw new IllegalArgumentException("Quarter outside valid range.");
140        }
141        this.year = (short) year.getYear();
142        this.quarter = (byte) quarter;
143        peg(Calendar.getInstance());
144    }
145
146    /**
147     * Constructs a new Quarter, based on a date/time and the default time zone.
148     *
149     * @param time  the date/time.
150     */
151    public Quarter(Date time) {
152        this(time, RegularTimePeriod.DEFAULT_TIME_ZONE);
153    }
154
155    /**
156     * Constructs a Quarter, based on a date/time and time zone.
157     *
158     * @param time  the date/time.
159     * @param zone  the zone (<code>null</code> not permitted).
160     */
161    public Quarter(Date time, TimeZone zone) {
162        Calendar calendar = Calendar.getInstance(zone);
163        calendar.setTime(time);
164        int month = calendar.get(Calendar.MONTH) + 1;
165        this.quarter = (byte) SerialDate.monthCodeToQuarter(month);
166        this.year = (short) calendar.get(Calendar.YEAR);
167        peg(calendar);
168    }
169
170    /**
171     * Returns the quarter.
172     *
173     * @return The quarter.
174     */
175    public int getQuarter() {
176        return this.quarter;
177    }
178
179    /**
180     * Returns the year.
181     *
182     * @return The year.
183     */
184    public Year getYear() {
185        return new Year(this.year);
186    }
187    
188    /**
189     * Returns the year.
190     * 
191     * @return The year.
192     * 
193     * @since 1.0.3
194     */
195    public int getYearValue() {
196        return this.year;
197    }
198
199    /**
200     * Returns the first millisecond of the quarter.  This will be determined 
201     * relative to the time zone specified in the constructor, or in the 
202     * calendar instance passed in the most recent call to the 
203     * {@link #peg(Calendar)} method.
204     *
205     * @return The first millisecond of the quarter.
206     * 
207     * @see #getLastMillisecond()
208     */
209    public long getFirstMillisecond() {
210        return this.firstMillisecond;
211    }
212
213    /**
214     * Returns the last millisecond of the quarter.  This will be 
215     * determined relative to the time zone specified in the constructor, or
216     * in the calendar instance passed in the most recent call to the 
217     * {@link #peg(Calendar)} method.
218     *
219     * @return The last millisecond of the quarter.
220     * 
221     * @see #getFirstMillisecond()
222     */
223    public long getLastMillisecond() {
224        return this.lastMillisecond;
225    }
226    
227    /** 
228     * Recalculates the start date/time and end date/time for this time period 
229     * relative to the supplied calendar (which incorporates a time zone).
230     * 
231     * @param calendar  the calendar (<code>null</code> not permitted).
232     * 
233     * @since 1.0.3
234     */
235    public void peg(Calendar calendar) {
236        this.firstMillisecond = getFirstMillisecond(calendar);
237        this.lastMillisecond = getLastMillisecond(calendar);
238    }
239
240    /**
241     * Returns the quarter preceding this one.
242     *
243     * @return The quarter preceding this one (or <code>null</code> if this is 
244     *     Q1 1900).
245     */
246    public RegularTimePeriod previous() {
247        Quarter result;
248        if (this.quarter > FIRST_QUARTER) {
249            result = new Quarter(this.quarter - 1, this.year);
250        }
251        else {
252            if (this.year > 1900) {
253                result = new Quarter(LAST_QUARTER, this.year - 1);
254            }
255            else {
256                result = null;
257            }
258        }
259        return result;
260    }
261
262    /**
263     * Returns the quarter following this one.
264     *
265     * @return The quarter following this one (or null if this is Q4 9999).
266     */
267    public RegularTimePeriod next() {
268        Quarter result;
269        if (this.quarter < LAST_QUARTER) {
270            result = new Quarter(this.quarter + 1, this.year);
271        }
272        else {
273            if (this.year < 9999) {
274                result = new Quarter(FIRST_QUARTER, this.year + 1);
275            }
276            else {
277                result = null;
278            }
279        }
280        return result;
281    }
282
283    /**
284     * Returns a serial index number for the quarter.
285     *
286     * @return The serial index number.
287     */
288    public long getSerialIndex() {
289        return this.year * 4L + this.quarter;
290    }
291
292    /**
293     * Tests the equality of this Quarter object to an arbitrary object.
294     * Returns <code>true</code> if the target is a Quarter instance 
295     * representing the same quarter as this object.  In all other cases, 
296     * returns <code>false</code>.
297     *
298     * @param obj  the object (<code>null</code> permitted).
299     *
300     * @return <code>true</code> if quarter and year of this and the object are
301     *         the same.
302     */
303    public boolean equals(Object obj) {
304
305        if (obj != null) {
306            if (obj instanceof Quarter) {
307                Quarter target = (Quarter) obj;
308                return (this.quarter == target.getQuarter()
309                        && (this.year == target.getYearValue()));
310            }
311            else {
312                return false;
313            }
314        }
315        else {
316            return false;
317        }
318
319    }
320
321    /**
322     * Returns a hash code for this object instance.  The approach described by
323     * Joshua Bloch in "Effective Java" has been used here:
324     * <p>
325     * <code>http://developer.java.sun.com/developer/Books/effectivejava
326     * /Chapter3.pdf</code>
327     * 
328     * @return A hash code.
329     */
330    public int hashCode() {
331        int result = 17;
332        result = 37 * result + this.quarter;
333        result = 37 * result + this.year;
334        return result;
335    }
336
337    /**
338     * Returns an integer indicating the order of this Quarter object relative
339     * to the specified object:
340     *
341     * negative == before, zero == same, positive == after.
342     *
343     * @param o1  the object to compare
344     *
345     * @return negative == before, zero == same, positive == after.
346     */
347    public int compareTo(Object o1) {
348
349        int result;
350
351        // CASE 1 : Comparing to another Quarter object
352        // --------------------------------------------
353        if (o1 instanceof Quarter) {
354            Quarter q = (Quarter) o1;
355            result = this.year - q.getYearValue();
356            if (result == 0) {
357                result = this.quarter - q.getQuarter();
358            }
359        }
360
361        // CASE 2 : Comparing to another TimePeriod object
362        // -----------------------------------------------
363        else if (o1 instanceof RegularTimePeriod) {
364            // more difficult case - evaluate later...
365            result = 0;
366        }
367
368        // CASE 3 : Comparing to a non-TimePeriod object
369        // ---------------------------------------------
370        else {
371            // consider time periods to be ordered after general objects
372            result = 1;
373        }
374
375        return result;
376
377    }
378
379    /**
380     * Returns a string representing the quarter (e.g. "Q1/2002").
381     *
382     * @return A string representing the quarter.
383     */
384    public String toString() {
385        return "Q" + this.quarter + "/" + this.year;
386    }
387
388    /**
389     * Returns the first millisecond in the Quarter, evaluated using the
390     * supplied calendar (which determines the time zone).
391     *
392     * @param calendar  the calendar (<code>null</code> not permitted).
393     *
394     * @return The first millisecond in the Quarter.
395     *
396     * @throws NullPointerException if <code>calendar</code> is 
397     *     <code>null</code>.
398     */
399    public long getFirstMillisecond(Calendar calendar) {
400        int month = Quarter.FIRST_MONTH_IN_QUARTER[this.quarter];
401        calendar.set(this.year, month - 1, 1, 0, 0, 0);
402        calendar.set(Calendar.MILLISECOND, 0);
403        // in the following line, we'd rather call calendar.getTimeInMillis()
404        // to avoid object creation, but that isn't supported in Java 1.3.1
405        return calendar.getTime().getTime();
406    }
407
408    /**
409     * Returns the last millisecond of the Quarter, evaluated using the
410     * supplied calendar (which determines the time zone).
411     *
412     * @param calendar  the calendar (<code>null</code> not permitted).
413     *
414     * @return The last millisecond of the Quarter.
415     *
416     * @throws NullPointerException if <code>calendar</code> is 
417     *     <code>null</code>.
418     */
419    public long getLastMillisecond(Calendar calendar) {
420        int month = Quarter.LAST_MONTH_IN_QUARTER[this.quarter];
421        int eom = SerialDate.lastDayOfMonth(month, this.year);
422        calendar.set(this.year, month - 1, eom, 23, 59, 59);
423        calendar.set(Calendar.MILLISECOND, 999);
424        // in the following line, we'd rather call calendar.getTimeInMillis()
425        // to avoid object creation, but that isn't supported in Java 1.3.1
426        return calendar.getTime().getTime();
427    }
428
429    /**
430     * Parses the string argument as a quarter.
431     * <P>
432     * This method should accept the following formats: "YYYY-QN" and "QN-YYYY",
433     * where the "-" can be a space, a forward-slash (/), comma or a dash (-).
434     * @param s A string representing the quarter.
435     *
436     * @return The quarter.
437     */
438    public static Quarter parseQuarter(String s) {
439
440        // find the Q and the integer following it (remove both from the
441        // string)...
442        int i = s.indexOf("Q");
443        if (i == -1) {
444            throw new TimePeriodFormatException("Missing Q.");
445        }
446
447        if (i == s.length() - 1) {
448            throw new TimePeriodFormatException("Q found at end of string.");
449        }
450
451        String qstr = s.substring(i + 1, i + 2);
452        int quarter = Integer.parseInt(qstr);
453        String remaining = s.substring(0, i) + s.substring(i + 2, s.length());
454
455        // replace any / , or - with a space
456        remaining = remaining.replace('/', ' ');
457        remaining = remaining.replace(',', ' ');
458        remaining = remaining.replace('-', ' ');
459
460        // parse the string...
461        Year year = Year.parseYear(remaining.trim());
462        Quarter result = new Quarter(quarter, year);
463        return result;
464
465    }
466
467}