Source for org.jfree.data.time.TimePeriodAnchor

   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:  * TimePeriodAnchor.java
  29:  * ---------------------
  30:  * (C) Copyright 2003-2007, by Object Refinery Limited.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * Changes:
  36:  * --------
  37:  * 30-Jul-2003 : Version 1 (DG);
  38:  * 01-Mar-2004 : Added readResolve() method (DG);
  39:  *
  40:  */
  41: 
  42: package org.jfree.data.time;
  43: 
  44: import java.io.ObjectStreamException;
  45: import java.io.Serializable;
  46: 
  47: /**
  48:  * Used to indicate one of three positions in a time period: 
  49:  * <code>START</code>, <code>MIDDLE</code> and <code>END</code>.
  50:  */
  51: public final class TimePeriodAnchor implements Serializable {
  52: 
  53:     /** For serialization. */
  54:     private static final long serialVersionUID = 2011955697457548862L;
  55:     
  56:     /** Start of period. */
  57:     public static final TimePeriodAnchor START 
  58:         = new TimePeriodAnchor("TimePeriodAnchor.START");
  59: 
  60:     /** Middle of period. */
  61:     public static final TimePeriodAnchor MIDDLE 
  62:         = new TimePeriodAnchor("TimePeriodAnchor.MIDDLE");
  63: 
  64:     /** End of period. */
  65:     public static final TimePeriodAnchor END 
  66:         = new TimePeriodAnchor("TimePeriodAnchor.END");
  67: 
  68:     /** The name. */
  69:     private String name;
  70: 
  71:     /**
  72:      * Private constructor.
  73:      *
  74:      * @param name  the name.
  75:      */
  76:     private TimePeriodAnchor(String name) {
  77:         this.name = name;
  78:     }
  79: 
  80:     /**
  81:      * Returns a string representing the object.
  82:      *
  83:      * @return The string.
  84:      */
  85:     public String toString() {
  86:         return this.name;
  87:     }
  88: 
  89:     /**
  90:      * Returns <code>true</code> if this object is equal to the specified 
  91:      * object, and <code>false</code> otherwise.
  92:      *
  93:      * @param obj  the other object.
  94:      *
  95:      * @return A boolean.
  96:      */
  97:     public boolean equals(Object obj) {
  98: 
  99:         if (this == obj) {
 100:             return true;
 101:         }
 102:         if (!(obj instanceof TimePeriodAnchor)) {
 103:             return false;
 104:         }
 105: 
 106:         TimePeriodAnchor position = (TimePeriodAnchor) obj;
 107:         if (!this.name.equals(position.name)) {
 108:             return false;
 109:         }
 110: 
 111:         return true;
 112:     }
 113: 
 114:     /**
 115:      * Returns a hash code value for the object.
 116:      *
 117:      * @return The hashcode
 118:      */
 119:     public int hashCode() {
 120:         return this.name.hashCode();
 121:     }
 122:     
 123:     /**
 124:      * Ensures that serialization returns the unique instances.
 125:      * 
 126:      * @return The object.
 127:      * 
 128:      * @throws ObjectStreamException if there is a problem.
 129:      */
 130:     private Object readResolve() throws ObjectStreamException {
 131:         if (this.equals(TimePeriodAnchor.START)) {
 132:             return TimePeriodAnchor.START;
 133:         }
 134:         else if (this.equals(TimePeriodAnchor.MIDDLE)) {
 135:             return TimePeriodAnchor.MIDDLE;
 136:         }
 137:         else if (this.equals(TimePeriodAnchor.END)) {
 138:             return TimePeriodAnchor.END;
 139:         }
 140:         return null;
 141:     }
 142: 
 143: }