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    
059    package org.jfree.data.time;
060    
061    import java.io.Serializable;
062    import java.util.Calendar;
063    import java.util.Date;
064    import java.util.TimeZone;
065    
066    import org.jfree.date.MonthConstants;
067    import 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     */
074    public 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    }