libjava/java/util/SimpleTimeZone.java

   1 /* Copyright (C) 1998, 1999  Cygnus Solutions
   2
   3    This file is part of libgcj.
   4
   5 This software is copyrighted work licensed under the terms of the
   6 Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
   7 details.  */
   8
   9 package java.util;
  10
  11 /**
  12  * @author Per Bothner <bothner@cygnus.com>
  13  * @date October 24, 1998.
  14  */
  15
  16 /* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3.
  17  * Status:  Does not know how to figure out if daylight savings time
  18  *   is in effect;  hence only correct for zones without DST.
  19  *   No known spec for hashCode.
  20  */
  21
  22 public class SimpleTimeZone extends TimeZone
  23 {
  24   // The fields are as specified in Sun's "Serialized Form"
  25   // in the JDK 1.2 beta 4 API specification.
  26
  27   int dstSavings = 60 * 60 * 1000;
  28
  29   int rawOffset;
  30
  31   // int serialVersionOnStream;
  32
  33   int startDay;
  34   int startDayOfWeek;
  35   int startMode;  /// Seems to be JDK 1.2 only.
  36
  37   int startMonth;
  38
  39   int startTime;
  40
  41   int startYear;
  42
  43   int endDay;
  44
  45   int endDayOfWeek;
  46
  47   int endMode;  // Seems to be JDK 1.2 only.
  48
  49   int endMonth;
  50
  51   int endTime;
  52
  53   // byte[] monthLength;
  54
  55   boolean useDaylight;
  56
  57   public SimpleTimeZone (int rawOffset, String ID)
  58   {
  59     setID(ID);
  60     this.rawOffset = rawOffset;
  61   }
  62
  63   public SimpleTimeZone (int rawOffset, String ID,
  64                          int startMonth, int startDay,
  65                          int startDayOfWeek, int startTime,
  66                          int endMonth, int endDay,
  67                          int endDayOfWeek, int endTime)
  68   {
  69     this(rawOffset, ID);
  70     setStartRule (startMonth, startDay, startDayOfWeek, startTime);
  71     setEndRule (endMonth, endDay, endDayOfWeek, endTime);
  72   }
  73
  74   public int getRawOffset() { return rawOffset; }
  75   public void setRawOffset (int offsetMillis) { rawOffset = offsetMillis; }
  76
  77   public int getOffset (int era, int year, int month, int day,
  78                         int dayOfWeek, int millis)
  79   {
  80     int offset = getRawOffset();
  81     if (useDaylight)
  82       {
  83         if (startYear != 0
  84             && (year < startYear || era == GregorianCalendar.BC))
  85           return offset;
  86         boolean midYearSummer = startMonth < endMonth;
  87         if (midYearSummer ? (month < startMonth || month > endMonth)
  88             : (month < startMonth && month > endMonth))
  89           return offset; // Definitely not DST.
  90         if (midYearSummer ? (month > startMonth && month < endMonth)
  91             : (month > startMonth || month < endMonth))
  92           return offset + dstSavings;  // Definitely DST.
  93         // Now it gets more complicated.  Bail for now.
  94         throw new Error("not implemented - SimpleTimeZone.getOffset");
  95       }
  96     return offset;
  97   }
  98
  99   public boolean useDaylightTime() { return useDaylight; }
 100
 101   public boolean inDaylightTime(Date date)
 102   {
 103     if (! useDaylight)
 104       return false;
 105     throw new Error("not implemented - SimpleTimeZone.inDaylightTime");
 106   }
 107
 108   public int getDSTSavings () { return dstSavings; }
 109
 110   public void setDSTSavings (int millisSavedDuringDST)
 111   { dstSavings = millisSavedDuringDST; }
 112
 113   public void setStartRule (int month, int dayOfWeekInMonth,
 114                             int dayOfWeek, int time)
 115   {
 116     this.startMonth = month;
 117     this.startDay = dayOfWeekInMonth;
 118     this.startDayOfWeek = dayOfWeek;
 119     this.startTime = time;
 120     this.useDaylight = true;
 121   }
 122
 123   public void setEndRule (int month, int dayOfWeekInMonth,
 124                             int dayOfWeek, int time)
 125   {
 126     this.endMonth = month;
 127     this.endDay = dayOfWeekInMonth;
 128     this.endDayOfWeek = dayOfWeek;
 129     this.endTime = time;
 130     this.useDaylight = true;
 131   }
 132
 133   public void setStartYear (int year)
 134   {
 135     this.startYear = startYear;
 136   }
 137
 138   public boolean hasSameRules (TimeZone other)
 139   {
 140     if (this == other)
 141       return true;
 142     if (! (other instanceof SimpleTimeZone))
 143       return false;
 144     SimpleTimeZone o = (SimpleTimeZone) other;
 145     if (rawOffset != o.rawOffset)
 146       return false;
 147     if (useDaylight != o.useDaylight)
 148       return false;
 149     if (! useDaylight)
 150       return true;
 151     return startDay == o.startDay
 152       && startDayOfWeek == o.startDayOfWeek
 153       && startMonth == o.startMonth
 154       && startTime == o.startTime
 155       && endDay == o.endDay
 156       && endDayOfWeek == o.endDayOfWeek
 157       && endMonth == o.endMonth
 158       && endTime == o.endTime
 159       && startYear == o.startYear
 160       && startMode == o.startMode
 161       && endMode == o.endMode;
 162   }
 163
 164   public boolean equals (Object obj)
 165   {
 166     if (! (obj instanceof SimpleTimeZone))
 167       return false;
 168     SimpleTimeZone other = (SimpleTimeZone) obj;
 169     return getID() == other.getID() && hasSameRules(other);
 170   }
 171
 172   public int hashCode ()
 173   {
 174     // FIXME - this does not folow any spec (since none is public)!
 175     int hash = rawOffset;
 176     if (useDaylight)
 177       hash += dstSavings + startYear + startMode + endMode
 178         + startDay + startDayOfWeek + startMonth + startTime
 179         + endDay + endDayOfWeek + endMonth + endTime;
 180     return hash;
 181   }
 182 }