    001    /* ===========================================================
    002     * JFreeChart : a free chart library for the Java(tm) platform
    003     * ===========================================================
    004     *
    005     * (C) Copyright 2000-2008, 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     * Week.java
    029     * ---------
    030     * (C) Copyright 2001-2008, by Object Refinery Limited and Contributors.
    031     *
    032     * Original Author:  David Gilbert (for Object Refinery Limited);
    033     * Contributor(s):   Aimin Han;
    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 : Worked on the parseWeek() method (DG);
    041     * 13-Feb-2002 : Fixed bug in Week(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     * 05-Apr-2002 : Reinstated this class to the JCommon library (DG);
    045     * 24-Jun-2002 : Removed unnecessary main method (DG);
    046     * 10-Sep-2002 : Added getSerialIndex() method (DG);
    047     * 06-Oct-2002 : Fixed errors reported by Checkstyle (DG);
    048     * 18-Oct-2002 : Changed to observe 52 or 53 weeks per year, consistent with
    049     *               GregorianCalendar. Thanks to Aimin Han for the code (DG);
    050     * 02-Jan-2003 : Removed debug code (DG);
    051     * 13-Mar-2003 : Moved to com.jrefinery.data.time package, and implemented
    052     *               Serializable (DG);
    053     * 21-Oct-2003 : Added hashCode() method (DG);
    054     * 24-May-2004 : Modified getFirstMillisecond() and getLastMillisecond() to
    055     *               take account of firstDayOfWeek setting in Java's Calendar
    056     *               class (DG);
    057     * 30-Sep-2004 : Replaced getTime().getTime() with getTimeInMillis() (DG);
    058     * 04-Nov-2004 : Reverted change of 30-Sep-2004, because it won't work for
    059     *               JDK 1.3 (DG);
    060     * ------------- JFREECHART 1.0.x ---------------------------------------------
    061     * 06-Mar-2006 : Fix for bug 1448828, incorrect calculation of week and year
    062     *               for the first few days of some years (DG);
    063     * 05-Oct-2006 : Updated API docs (DG);
    064     * 06-Oct-2006 : Refactored to cache first and last millisecond values (DG);
    065     * 09-Jan-2007 : Fixed bug in next() (DG);
    066     * 28-Aug-2007 : Added new constructor to avoid problem in creating new
    067     *               instances (DG);
    068     * 19-Dec-2007 : Fixed bug in deprecated constructor (DG);
    069     * 16-Sep-2008 : Deprecated DEFAULT_TIME_ZONE (DG);
    070     *
    071     */
    072
    073    package org.jfree.data.time;
    074
    075    import java.io.Serializable;
    076    import java.util.Calendar;
    077    import java.util.Date;
    078    import java.util.Locale;
    079    import java.util.TimeZone;
    080
    081    /**
    082     * A calendar week.  All years are considered to have 53 weeks, numbered from 1
    083     * to 53, although in many cases the 53rd week is empty.  Most of the time, the
    084     * 1st week of the year *begins* in the previous calendar year, but it always
    085     * finishes in the current year (this behaviour matches the workings of the
    086     * <code>GregorianCalendar</code> class).
    087     * <P>
    088     * This class is immutable, which is a requirement for all
    089     * {@link RegularTimePeriod} subclasses.
    090     */
    091    public class Week extends RegularTimePeriod implements Serializable {
    092
    093        /** For serialization. */
    094        private static final long serialVersionUID = 1856387786939865061L;
    095
    096        /** Constant for the first week in the year. */
    097        public static final int FIRST_WEEK_IN_YEAR = 1;
    098
    099        /** Constant for the last week in the year. */
    100        public static final int LAST_WEEK_IN_YEAR = 53;
    101
    102        /** The year in which the week falls. */
    103        private short year;
    104
    105        /** The week (1-53). */
    106        private byte week;
    107
    108        /** The first millisecond. */
    109        private long firstMillisecond;
    110
    111        /** The last millisecond. */
    112        private long lastMillisecond;
    113
    114        /**
    115         * Creates a new time period for the week in which the current system
    116         * date/time falls.
    117         */
    118        public Week() {
    119            this(new Date());
    120        }
    121
    122        /**
    123         * Creates a time period representing the week in the specified year.
    124         *
    125         * @param week  the week (1 to 53).
    126         * @param year  the year (1900 to 9999).
    127         */
    128        public Week(int week, int year) {
    129            if ((week < FIRST_WEEK_IN_YEAR) && (week > LAST_WEEK_IN_YEAR)) {
    130                throw new IllegalArgumentException(
    131                        "The 'week' argument must be in the range 1 - 53.");
    132            }
    133            this.week = (byte) week;
    134            this.year = (short) year;
    135            peg(Calendar.getInstance());
    136        }
    137
    138        /**
    139         * Creates a time period representing the week in the specified year.
    140         *
    141         * @param week  the week (1 to 53).
    142         * @param year  the year (1900 to 9999).
    143         */
    144        public Week(int week, Year year) {
    145            if ((week < FIRST_WEEK_IN_YEAR) && (week > LAST_WEEK_IN_YEAR)) {
    146                throw new IllegalArgumentException(
    147                        "The 'week' argument must be in the range 1 - 53.");
    148            }
    149            this.week = (byte) week;
    150            this.year = (short) year.getYear();
    151            peg(Calendar.getInstance());
    152       }
    153
    154        /**
    155         * Creates a time period for the week in which the specified date/time
    156         * falls, using the default time zone and locale (the locale can affect the
    157         * day-of-the-week that marks the beginning of the week, as well as the
    158         * minimal number of days in the first week of the year).
    159         *
    160         * @param time  the time (<code>null</code> not permitted).
    161         *
    162         * @see #Week(Date, TimeZone, Locale)
    163         */
    164        public Week(Date time) {
    165            // defer argument checking...
    166            this(time, TimeZone.getDefault(), Locale.getDefault());
    167        }
    168
    169        /**
    170         * Creates a time period for the week in which the specified date/time
    171         * falls, calculated relative to the specified time zone.
    172         *
    173         * @param time  the date/time (<code>null</code> not permitted).
    174         * @param zone  the time zone (<code>null</code> not permitted).
    175         *
    176         * @deprecated As of 1.0.7, use {@link #Week(Date, TimeZone, Locale)}.
    177         */
    178        public Week(Date time, TimeZone zone) {
    179            // defer argument checking...
    180            this(time, zone, Locale.getDefault());
    181        }
    182
    183        /**
    184         * Creates a time period for the week in which the specified date/time
    185         * falls, calculated relative to the specified time zone.
    186         *
    187         * @param time  the date/time (<code>null</code> not permitted).
    188         * @param zone  the time zone (<code>null</code> not permitted).
    189         * @param locale  the locale (<code>null</code> not permitted).
    190         *
    191         * @since 1.0.7
    192         */
    193        public Week(Date time, TimeZone zone, Locale locale) {
    194            if (time == null) {
    195                throw new IllegalArgumentException("Null 'time' argument.");
    196            }
    197            if (zone == null) {
    198                throw new IllegalArgumentException("Null 'zone' argument.");
    199            }
    200            if (locale == null) {
    201                throw new IllegalArgumentException("Null 'locale' argument.");
    202            }
    203            Calendar calendar = Calendar.getInstance(zone, locale);
    204            calendar.setTime(time);
    205
    206            // sometimes the last few days of the year are considered to fall in
    207            // the *first* week of the following year.  Refer to the Javadocs for
    208            // GregorianCalendar.
    209            int tempWeek = calendar.get(Calendar.WEEK_OF_YEAR);
    210            if (tempWeek == 1
    211                    && calendar.get(Calendar.MONTH) == Calendar.DECEMBER) {
    212                this.week = 1;
    213                this.year = (short) (calendar.get(Calendar.YEAR) + 1);
    214            }
    215            else {
    216                this.week = (byte) Math.min(tempWeek, LAST_WEEK_IN_YEAR);
    217                int yyyy = calendar.get(Calendar.YEAR);
    218                // alternatively, sometimes the first few days of the year are
    219                // considered to fall in the *last* week of the previous year...
    220                if (calendar.get(Calendar.MONTH) == Calendar.JANUARY
    221                        && this.week >= 52) {
    222                    yyyy--;
    223                }
    224                this.year = (short) yyyy;
    225            }
    226            peg(calendar);
    227        }
    228
    229        /**
    230         * Returns the year in which the week falls.
    231         *
    232         * @return The year (never <code>null</code>).
    233         */
    234        public Year getYear() {
    235            return new Year(this.year);
    236        }
    237
    238        /**
    239         * Returns the year in which the week falls, as an integer value.
    240         *
    241         * @return The year.
    242         */
    243        public int getYearValue() {
    244            return this.year;
    245        }
    246
    247        /**
    248         * Returns the week.
    249         *
    250         * @return The week.
    251         */
    252        public int getWeek() {
    253            return this.week;
    254        }
    255
    256        /**
    257         * Returns the first millisecond of the week.  This will be determined
    258         * relative to the time zone specified in the constructor, or in the
    259         * calendar instance passed in the most recent call to the
    260         * {@link #peg(Calendar)} method.
    261         *
    262         * @return The first millisecond of the week.
    263         *
    264         * @see #getLastMillisecond()
    265         */
    266        public long getFirstMillisecond() {
    267            return this.firstMillisecond;
    268        }
    269
    270        /**
    271         * Returns the last millisecond of the week.  This will be
    272         * determined relative to the time zone specified in the constructor, or
    273         * in the calendar instance passed in the most recent call to the
    274         * {@link #peg(Calendar)} method.
    275         *
    276         * @return The last millisecond of the week.
    277         *
    278         * @see #getFirstMillisecond()
    279         */
    280        public long getLastMillisecond() {
    281            return this.lastMillisecond;
    282        }
    283
    284        /**
    285         * Recalculates the start date/time and end date/time for this time period
    286         * relative to the supplied calendar (which incorporates a time zone).
    287         *
    288         * @param calendar  the calendar (<code>null</code> not permitted).
    289         *
    290         * @since 1.0.3
    291         */
    292        public void peg(Calendar calendar) {
    293            this.firstMillisecond = getFirstMillisecond(calendar);
    294            this.lastMillisecond = getLastMillisecond(calendar);
    295        }
    296
    297        /**
    298         * Returns the week preceding this one.  This method will return
    299         * <code>null</code> for some lower limit on the range of weeks (currently
    300         * week 1, 1900).  For week 1 of any year, the previous week is always week
    301         * 53, but week 53 may not contain any days (you should check for this).
    302         *
    303         * @return The preceding week (possibly <code>null</code>).
    304         */
    305        public RegularTimePeriod previous() {
    306
    307            Week result;
    308            if (this.week != FIRST_WEEK_IN_YEAR) {
    309                result = new Week(this.week - 1, this.year);
    310            }
    311            else {
    312                // we need to work out if the previous year has 52 or 53 weeks...
    313                if (this.year > 1900) {
    314                    int yy = this.year - 1;
    315                    Calendar prevYearCalendar = Calendar.getInstance();
    316                    prevYearCalendar.set(yy, Calendar.DECEMBER, 31);
    317                    result = new Week(prevYearCalendar.getActualMaximum(
    318                            Calendar.WEEK_OF_YEAR), yy);
    319                }
    320                else {
    321                    result = null;
    322                }
    323            }
    324            return result;
    325
    326        }
    327
    328        /**
    329         * Returns the week following this one.  This method will return
    330         * <code>null</code> for some upper limit on the range of weeks (currently
    331         * week 53, 9999).  For week 52 of any year, the following week is always
    332         * week 53, but week 53 may not contain any days (you should check for
    333         * this).
    334         *
    335         * @return The following week (possibly <code>null</code>).
    336         */
    337        public RegularTimePeriod next() {
    338
    339            Week result;
    340            if (this.week < 52) {
    341                result = new Week(this.week + 1, this.year);
    342            }
    343            else {
    344                Calendar calendar = Calendar.getInstance();
    345                calendar.set(this.year, Calendar.DECEMBER, 31);
    346                int actualMaxWeek
    347                    = calendar.getActualMaximum(Calendar.WEEK_OF_YEAR);
    348                if (this.week < actualMaxWeek) {
    349                    result = new Week(this.week + 1, this.year);
    350                }
    351                else {
    352                    if (this.year < 9999) {
    353                        result = new Week(FIRST_WEEK_IN_YEAR, this.year + 1);
    354                    }
    355                    else {
    356                        result = null;
    357                    }
    358                }
    359            }
    360            return result;
    361
    362        }
    363
    364        /**
    365         * Returns a serial index number for the week.
    366         *
    367         * @return The serial index number.
    368         */
    369        public long getSerialIndex() {
    370            return this.year * 53L + this.week;
    371        }
    372
    373        /**
    374         * Returns the first millisecond of the week, evaluated using the supplied
    375         * calendar (which determines the time zone).
    376         *
    377         * @param calendar  the calendar (<code>null</code> not permitted).
    378         *
    379         * @return The first millisecond of the week.
    380         *
    381         * @throws NullPointerException if <code>calendar</code> is
    382         *     <code>null</code>.
    383         */
    384        public long getFirstMillisecond(Calendar calendar) {
    385            Calendar c = (Calendar) calendar.clone();
    386            c.clear();
    387            c.set(Calendar.YEAR, this.year);
    388            c.set(Calendar.WEEK_OF_YEAR, this.week);
    389            c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek());
    390            c.set(Calendar.HOUR, 0);
    391            c.set(Calendar.MINUTE, 0);
    392            c.set(Calendar.SECOND, 0);
    393            c.set(Calendar.MILLISECOND, 0);
    394            //return c.getTimeInMillis();  // this won't work for JDK 1.3
    395            return c.getTime().getTime();
    396        }
    397
    398        /**
    399         * Returns the last millisecond of the week, evaluated using the supplied
    400         * calendar (which determines the time zone).
    401         *
    402         * @param calendar  the calendar (<code>null</code> not permitted).
    403         *
    404         * @return The last millisecond of the week.
    405         *
    406         * @throws NullPointerException if <code>calendar</code> is
    407         *     <code>null</code>.
    408         */
    409        public long getLastMillisecond(Calendar calendar) {
    410            Calendar c = (Calendar) calendar.clone();
    411            c.clear();
    412            c.set(Calendar.YEAR, this.year);
    413            c.set(Calendar.WEEK_OF_YEAR, this.week + 1);
    414            c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek());
    415            c.set(Calendar.HOUR, 0);
    416            c.set(Calendar.MINUTE, 0);
    417            c.set(Calendar.SECOND, 0);
    418            c.set(Calendar.MILLISECOND, 0);
    419            //return c.getTimeInMillis();  // this won't work for JDK 1.3
    420            return c.getTime().getTime() - 1;
    421        }
    422
    423        /**
    424         * Returns a string representing the week (e.g. "Week 9, 2002").
    425         *
    426         * TODO: look at internationalisation.
    427         *
    428         * @return A string representing the week.
    429         */
    430        public String toString() {
    431            return "Week " + this.week + ", " + this.year;
    432        }
    433
    434        /**
    435         * Tests the equality of this Week object to an arbitrary object.  Returns
    436         * true if the target is a Week instance representing the same week as this
    437         * object.  In all other cases, returns false.
    438         *
    439         * @param obj  the object (<code>null</code> permitted).
    440         *
    441         * @return <code>true</code> if week and year of this and object are the
    442         *         same.
    443         */
    444        public boolean equals(Object obj) {
    445
    446            if (obj == this) {
    447                return true;
    448            }
    449            if (!(obj instanceof Week)) {
    450                return false;
    451            }
    452            Week that = (Week) obj;
    453            if (this.week != that.week) {
    454                return false;
    455            }
    456            if (this.year != that.year) {
    457                return false;
    458            }
    459            return true;
    460
    461        }
    462
    463        /**
    464         * Returns a hash code for this object instance.  The approach described by
    465         * Joshua Bloch in "Effective Java" has been used here:
    466         * <p>
    467         * <code>http://developer.java.sun.com/developer/Books/effectivejava
    468         * /Chapter3.pdf</code>
    469         *
    470         * @return A hash code.
    471         */
    472        public int hashCode() {
    473            int result = 17;
    474            result = 37 * result + this.week;
    475            result = 37 * result + this.year;
    476            return result;
    477        }
    478
    479        /**
    480         * Returns an integer indicating the order of this Week object relative to
    481         * the specified object:
    482         *
    483         * negative == before, zero == same, positive == after.
    484         *
    485         * @param o1  the object to compare.
    486         *
    487         * @return negative == before, zero == same, positive == after.
    488         */
    489        public int compareTo(Object o1) {
    490
    491            int result;
    492
    493            // CASE 1 : Comparing to another Week object
    494            // --------------------------------------------
    495            if (o1 instanceof Week) {
    496                Week w = (Week) o1;
    497                result = this.year - w.getYear().getYear();
    498                if (result == 0) {
    499                    result = this.week - w.getWeek();
    500                }
    501            }
    502
    503            // CASE 2 : Comparing to another TimePeriod object
    504            // -----------------------------------------------
    505            else if (o1 instanceof RegularTimePeriod) {
    506                // more difficult case - evaluate later...
    507                result = 0;
    508            }
    509
    510            // CASE 3 : Comparing to a non-TimePeriod object
    511            // ---------------------------------------------
    512            else {
    513                // consider time periods to be ordered after general objects
    514                result = 1;
    515            }
    516
    517            return result;
    518
    519        }
    520
    521        /**
    522         * Parses the string argument as a week.
    523         * <P>
    524         * This method is required to accept the format "YYYY-Wnn".  It will also
    525         * accept "Wnn-YYYY". Anything else, at the moment, is a bonus.
    526         *
    527         * @param s  string to parse.
    528         *
    529         * @return <code>null</code> if the string is not parseable, the week
    530         *         otherwise.
    531         */
    532        public static Week parseWeek(String s) {
    533
    534            Week result = null;
    535            if (s != null) {
    536
    537                // trim whitespace from either end of the string
    538                s = s.trim();
    539
    540                int i = Week.findSeparator(s);
    541                if (i != -1) {
    542                    String s1 = s.substring(0, i).trim();
    543                    String s2 = s.substring(i + 1, s.length()).trim();
    544
    545                    Year y = Week.evaluateAsYear(s1);
    546                    int w;
    547                    if (y != null) {
    548                        w = Week.stringToWeek(s2);
    549                        if (w == -1) {
    550                            throw new TimePeriodFormatException(
    551                                    "Can't evaluate the week.");
    552                        }
    553                        result = new Week(w, y);
    554                    }
    555                    else {
    556                        y = Week.evaluateAsYear(s2);
    557                        if (y != null) {
    558                            w = Week.stringToWeek(s1);
    559                            if (w == -1) {
    560                                throw new TimePeriodFormatException(
    561                                        "Can't evaluate the week.");
    562                            }
    563                            result = new Week(w, y);
    564                        }
    565                        else {
    566                            throw new TimePeriodFormatException(
    567                                    "Can't evaluate the year.");
    568                        }
    569                    }
    570
    571                }
    572                else {
    573                    throw new TimePeriodFormatException(
    574                            "Could not find separator.");
    575                }
    576
    577            }
    578            return result;
    579
    580        }
    581
    582        /**
    583         * Finds the first occurrence of ' ', '-', ',' or '.'
    584         *
    585         * @param s  the string to parse.
    586         *
    587         * @return <code>-1</code> if none of the characters was found, the
    588         *      index of the first occurrence otherwise.
    589         */
    590        private static int findSeparator(String s) {
    591
    592            int result = s.indexOf('-');
    593            if (result == -1) {
    594                result = s.indexOf(',');
    595            }
    596            if (result == -1) {
    597                result = s.indexOf(' ');
    598            }
    599            if (result == -1) {
    600                result = s.indexOf('.');
    601            }
    602            return result;
    603        }
    604
    605        /**
    606         * Creates a year from a string, or returns null (format exceptions
    607         * suppressed).
    608         *
    609         * @param s  string to parse.
    610         *
    611         * @return <code>null</code> if the string is not parseable, the year
    612         *         otherwise.
    613         */
    614        private static Year evaluateAsYear(String s) {
    615
    616            Year result = null;
    617            try {
    618                result = Year.parseYear(s);
    619            }
    620            catch (TimePeriodFormatException e) {
    621                // suppress
    622            }
    623            return result;
    624
    625        }
    626
    627        /**
    628         * Converts a string to a week.
    629         *
    630         * @param s  the string to parse.
    631         * @return <code>-1</code> if the string does not contain a week number,
    632         *         the number of the week otherwise.
    633         */
    634        private static int stringToWeek(String s) {
    635
    636            int result = -1;
    637            s = s.replace('W', ' ');
    638            s = s.trim();
    639            try {
    640                result = Integer.parseInt(s);
    641                if ((result < 1) || (result > LAST_WEEK_IN_YEAR)) {
    642                    result = -1;
    643                }
    644            }
    645            catch (NumberFormatException e) {
    646                // suppress
    647            }
    648            return result;
    649
    650        }
    651
    652    }