Source for org.jfree.chart.axis.MonthDateFormat

   1: /* ===========================================================
   2:  * JFreeChart : a free chart library for the Java(tm) platform
   3:  * ===========================================================
   4:  *
   5:  * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
   6:  *
   7:  * Project Info:  http://www.jfree.org/jfreechart/index.html
   8:  *
   9:  * This library is free software; you can redistribute it and/or modify it 
  10:  * under the terms of the GNU Lesser General Public License as published by 
  11:  * the Free Software Foundation; either version 2.1 of the License, or 
  12:  * (at your option) any later version.
  13:  *
  14:  * This library is distributed in the hope that it will be useful, but 
  15:  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
  16:  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
  17:  * License for more details.
  18:  *
  19:  * You should have received a copy of the GNU Lesser General Public
  20:  * License along with this library; if not, write to the Free Software
  21:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
  22:  * USA.  
  23:  *
  24:  * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
  25:  * in the United States and other countries.]
  26:  *
  27:  * --------------------
  28:  * MonthDateFormat.java
  29:  * --------------------
  30:  * (C) Copyright 2005-2007, by Object Refinery Limited and Contributors.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * $Id: MonthDateFormat.java,v 1.1.2.4 2007/01/17 15:11:07 mungady Exp $
  36:  *
  37:  * Changes:
  38:  * --------
  39:  * 10-May-2005 : Version 1 (DG);
  40:  *
  41:  */
  42: 
  43: package org.jfree.chart.axis;
  44: 
  45: import java.text.DateFormat;
  46: import java.text.DateFormatSymbols;
  47: import java.text.FieldPosition;
  48: import java.text.NumberFormat;
  49: import java.text.ParsePosition;
  50: import java.text.SimpleDateFormat;
  51: import java.util.Arrays;
  52: import java.util.Calendar;
  53: import java.util.Date;
  54: import java.util.GregorianCalendar;
  55: import java.util.Locale;
  56: import java.util.TimeZone;
  57: 
  58: import org.jfree.data.time.Month;
  59: 
  60: /**
  61:  * A formatter that formats dates to show the initial letter(s) of the month
  62:  * name and, as an option, the year for the first or last month of each year.
  63:  */
  64: public class MonthDateFormat extends DateFormat {
  65:     
  66:     /** The symbols used for the months. */
  67:     private String[] months;
  68:     
  69:     /** Flags that control which months will have the year appended. */
  70:     private boolean[] showYear;
  71:     
  72:     /** The year formatter. */
  73:     private DateFormat yearFormatter;
  74:     
  75:     /**
  76:      * Creates a new instance for the default time zone.
  77:      */
  78:     public MonthDateFormat() {
  79:         this(TimeZone.getDefault());  
  80:     }
  81:     
  82:     /**
  83:      * Creates a new instance for the specified time zone.
  84:      * 
  85:      * @param zone  the time zone (<code>null</code> not permitted).
  86:      */
  87:     public MonthDateFormat(TimeZone zone) {
  88:         this(zone, Locale.getDefault(), 1, true, false);
  89:     }
  90:     
  91:     /**
  92:      * Creates a new instance for the specified time zone.
  93:      * 
  94:      * @param locale  the locale used to obtain the month 
  95:      *                names (<code>null</code> not permitted).
  96:      */
  97:     public MonthDateFormat(Locale locale) {
  98:         this(TimeZone.getDefault(), locale, 1, true, false);
  99:     }
 100:     
 101:     /**
 102:      * Creates a new instance for the specified time zone.
 103:      * 
 104:      * @param zone  the time zone (<code>null</code> not permitted).
 105:      * @param chars  the maximum number of characters to use from the month
 106:      *               names (that are obtained from the date symbols of the
 107:      *               default locale).  If this value is <= 0, the entire 
 108:      *               month name is used in each case.
 109:      */
 110:     public MonthDateFormat(TimeZone zone, int chars) {
 111:         this(zone, Locale.getDefault(), chars, true, false);
 112:     }
 113:     
 114:     /**
 115:      * Creates a new instance for the specified time zone.
 116:      * 
 117:      * @param locale  the locale (<code>null</code> not permitted).
 118:      * @param chars  the maximum number of characters to use from the month
 119:      *               names (that are obtained from the date symbols of the
 120:      *               default locale).  If this value is <= 0, the entire 
 121:      *               month name is used in each case.
 122:      */
 123:     public MonthDateFormat(Locale locale, int chars) {
 124:         this(TimeZone.getDefault(), locale, chars, true, false);
 125:     }
 126: 
 127:     /**
 128:      * Creates a new formatter.
 129:      * 
 130:      * @param zone  the time zone used to extract the month and year from dates
 131:      *              passed to this formatter (<code>null</code> not permitted).
 132:      * @param locale  the locale used to determine the month names 
 133:      *                (<code>null</code> not permitted).
 134:      * @param chars  the maximum number of characters to use from the month 
 135:      *               names, or zero to indicate that the entire month name 
 136:      *               should be used.
 137:      * @param showYearForJan  a flag that controls whether or not the year is
 138:      *                        appended to the symbol for the first month of
 139:      *                        each year.
 140:      * @param showYearForDec  a flag that controls whether or not the year is
 141:      *                        appended to the symbol for the last month of
 142:      *                        each year.
 143:      */
 144:     public MonthDateFormat(TimeZone zone, Locale locale, int chars, 
 145:                            boolean showYearForJan, boolean showYearForDec) {
 146:         this(zone, locale, chars, new boolean[] {showYearForJan, false, false, 
 147:             false, false, false, false, false, false, false, false, false,
 148:             showYearForDec}, new SimpleDateFormat("yy"));       
 149:     }
 150:     
 151:     /**
 152:      * Creates a new formatter.
 153:      * 
 154:      * @param zone  the time zone used to extract the month and year from dates
 155:      *              passed to this formatter (<code>null</code> not permitted).
 156:      * @param locale  the locale used to determine the month names 
 157:      *                (<code>null</code> not permitted).
 158:      * @param chars  the maximum number of characters to use from the month 
 159:      *               names, or zero to indicate that the entire month name 
 160:      *               should be used.
 161:      * @param showYear  an array of flags that control whether or not the
 162:      *                  year is displayed for a particular month.
 163:      * @param yearFormatter  the year formatter.
 164:      */
 165:     public MonthDateFormat(TimeZone zone, Locale locale, int chars, 
 166:                            boolean[] showYear, DateFormat yearFormatter) {
 167:         if (locale == null) {
 168:             throw new IllegalArgumentException("Null 'locale' argument.");
 169:         }
 170:         DateFormatSymbols dfs = new DateFormatSymbols(locale);
 171:         String[] monthsFromLocale = dfs.getMonths();
 172:         this.months = new String[12];
 173:         for (int i = 0; i < 12; i++) {
 174:             if (chars > 0) {
 175:                 months[i] = monthsFromLocale[i].substring(0, 
 176:                         Math.min(chars, monthsFromLocale[i].length()));
 177:             }
 178:             else {
 179:                 months[i] = monthsFromLocale[i];
 180:             }
 181:         }
 182:         this.calendar = new GregorianCalendar(zone);
 183:         this.showYear = showYear;
 184:         this.yearFormatter = yearFormatter; 
 185:         
 186:         // the following is never used, but it seems that DateFormat requires
 187:         // it to be non-null.  It isn't well covered in the spec, refer to 
 188:         // bug parade 5061189 for more info.
 189:         this.numberFormat = NumberFormat.getNumberInstance();
 190:     }
 191: 
 192:     /**
 193:      * Formats the given date.
 194:      * 
 195:      * @param date  the date.
 196:      * @param toAppendTo  the string buffer.
 197:      * @param fieldPosition  the field position.
 198:      * 
 199:      * @return The formatted date.
 200:      */
 201:     public StringBuffer format(Date date, StringBuffer toAppendTo,
 202:                                FieldPosition fieldPosition) {
 203:         this.calendar.setTime(date);
 204:         int month = this.calendar.get(Calendar.MONTH);
 205:         toAppendTo.append(this.months[month]);
 206:         if (this.showYear[month]) {
 207:             toAppendTo.append(this.yearFormatter.format(date));
 208:         }
 209:         return toAppendTo;   
 210:     }
 211: 
 212:     /**
 213:      * Parses the given string (not implemented).
 214:      * 
 215:      * @param source  the date string.
 216:      * @param pos  the parse position.
 217:      * 
 218:      * @return <code>null</code>, as this method has not been implemented.
 219:      */
 220:     public Date parse(String source, ParsePosition pos) {
 221:         return null;   
 222:     }
 223: 
 224:     /**
 225:      * Tests this formatter for equality with an arbitrary object.
 226:      * 
 227:      * @param obj  the object.
 228:      * 
 229:      * @return A boolean.
 230:      */
 231:     public boolean equals(Object obj) {
 232:         if (obj == this) {
 233:             return true;
 234:         }
 235:         if (!(obj instanceof MonthDateFormat)) {
 236:             return false;
 237:         }
 238:         if (!super.equals(obj)) {
 239:             return false;
 240:         }
 241:         MonthDateFormat that = (MonthDateFormat) obj;
 242:         if (!Arrays.equals(this.months, that.months)) {
 243:             return false;
 244:         }
 245:         if (!Arrays.equals(this.showYear, that.showYear)) {
 246:             return false;
 247:         }
 248:         if (!this.yearFormatter.equals(that.yearFormatter)) {
 249:             return false;
 250:         }
 251:         return true;
 252:     }
 253: 
 254:     /**
 255:      * Some test code.
 256:      * 
 257:      * @param args  ignored.
 258:      */
 259:     public static void main(String[] args) {
 260:         MonthDateFormat mdf = new MonthDateFormat(Locale.UK, 2);
 261:         System.out.println("UK:");
 262:         System.out.println(mdf.format(new Month(1, 2005).getStart()));      
 263:         System.out.println(mdf.format(new Month(2, 2005).getStart()));      
 264:         System.out.println(mdf.format(new Month(3, 2005).getStart()));      
 265:         System.out.println(mdf.format(new Month(4, 2005).getStart()));      
 266:         System.out.println(mdf.format(new Month(5, 2005).getStart()));      
 267:         System.out.println(mdf.format(new Month(6, 2005).getStart()));      
 268:         System.out.println(mdf.format(new Month(7, 2005).getStart()));      
 269:         System.out.println(mdf.format(new Month(8, 2005).getStart()));      
 270:         System.out.println(mdf.format(new Month(9, 2005).getStart()));      
 271:         System.out.println(mdf.format(new Month(10, 2005).getStart()));     
 272:         System.out.println(mdf.format(new Month(11, 2005).getStart()));     
 273:         System.out.println(mdf.format(new Month(12, 2005).getStart()));  
 274:         System.out.println();
 275: 
 276:         mdf = new MonthDateFormat(Locale.GERMANY, 2);
 277:         System.out.println("GERMANY:");
 278:         System.out.println(mdf.format(new Month(1, 2005).getStart()));      
 279:         System.out.println(mdf.format(new Month(2, 2005).getStart()));      
 280:         System.out.println(mdf.format(new Month(3, 2005).getStart()));      
 281:         System.out.println(mdf.format(new Month(4, 2005).getStart()));      
 282:         System.out.println(mdf.format(new Month(5, 2005).getStart()));      
 283:         System.out.println(mdf.format(new Month(6, 2005).getStart()));      
 284:         System.out.println(mdf.format(new Month(7, 2005).getStart()));      
 285:         System.out.println(mdf.format(new Month(8, 2005).getStart()));      
 286:         System.out.println(mdf.format(new Month(9, 2005).getStart()));      
 287:         System.out.println(mdf.format(new Month(10, 2005).getStart()));     
 288:         System.out.println(mdf.format(new Month(11, 2005).getStart()));     
 289:         System.out.println(mdf.format(new Month(12, 2005).getStart()));  
 290:         System.out.println();
 291:         
 292:         mdf = new MonthDateFormat(Locale.FRANCE, 2);
 293:         System.out.println("FRANCE:");
 294:         System.out.println(mdf.format(new Month(1, 2005).getStart()));      
 295:         System.out.println(mdf.format(new Month(2, 2005).getStart()));      
 296:         System.out.println(mdf.format(new Month(3, 2005).getStart()));      
 297:         System.out.println(mdf.format(new Month(4, 2005).getStart()));      
 298:         System.out.println(mdf.format(new Month(5, 2005).getStart()));      
 299:         System.out.println(mdf.format(new Month(6, 2005).getStart()));      
 300:         System.out.println(mdf.format(new Month(7, 2005).getStart()));      
 301:         System.out.println(mdf.format(new Month(8, 2005).getStart()));      
 302:         System.out.println(mdf.format(new Month(9, 2005).getStart()));      
 303:         System.out.println(mdf.format(new Month(10, 2005).getStart()));     
 304:         System.out.println(mdf.format(new Month(11, 2005).getStart()));     
 305:         System.out.println(mdf.format(new Month(12, 2005).getStart()));  
 306:         System.out.println();
 307:         
 308:         SimpleDateFormat sdf = new SimpleDateFormat("yyyy");
 309:         sdf.setNumberFormat(null);
 310:         System.out.println(sdf.equals("X"));
 311:     }
 312: }