    001/* ===========================================================
    002 * JFreeChart : a free chart library for the Java(tm) platform
    003 * ===========================================================
    004 *
    005 * (C) Copyright 2000-2011, 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 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
    025 * Other names may be trademarks of their respective owners.]
    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
    073package org.jfree.data.time;
    074
    075import java.io.Serializable;
    076import java.util.Calendar;
    077import java.util.Date;
    078import java.util.Locale;
    079import 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 */
    091public 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}