Source for org.jfree.data.statistics.HistogramType

   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:  * HistogramType.java
  29:  * ------------------
  30:  * (C) Copyright 2004-2007, by Object Refinery Limited and Contributors.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * Changes
  36:  * -------
  37:  * 05-Mar-2004 : Version 1 (DG);
  38:  * 
  39:  */
  40: 
  41: package org.jfree.data.statistics;
  42: 
  43: import java.io.ObjectStreamException;
  44: import java.io.Serializable;
  45:     
  46: /**
  47:  * A class for creating constants to represent the histogram type.  See Bloch's
  48:  * enum tip in 'Effective Java'.
  49:  */
  50: public class HistogramType implements Serializable { 
  51:         
  52:     /** For serialization. */
  53:     private static final long serialVersionUID = 2618927186251997727L;
  54:     
  55:     /** Frequency histogram. */
  56:     public static final HistogramType FREQUENCY 
  57:         = new HistogramType("FREQUENCY");
  58:     
  59:     /** Relative frequency. */
  60:     public static final HistogramType RELATIVE_FREQUENCY 
  61:         = new HistogramType("RELATIVE_FREQUENCY");
  62:     
  63:     /** Scale area to one. */
  64:     public static final HistogramType SCALE_AREA_TO_1 
  65:         = new HistogramType("SCALE_AREA_TO_1");
  66: 
  67:     /** The type name. */
  68:     private String name;
  69:         
  70:     /** 
  71:      * Creates a new type.
  72:      * 
  73:      * @param name  the name.
  74:      */
  75:     private HistogramType(String name) {
  76:         this.name = name;
  77:     } 
  78: 
  79:     /**
  80:      * Returns a string representing the object.
  81:      *
  82:      * @return The string.
  83:      */
  84:     public String toString() {
  85:         return this.name;
  86:     }
  87: 
  88:     /**
  89:      * Tests this type for equality with an arbitrary object.
  90:      *
  91:      * @param obj  the object to test against.
  92:      *
  93:      * @return A boolean.
  94:      */
  95:     public boolean equals(Object obj) {
  96:         
  97:         if (obj == null) {
  98:             return false;   
  99:         }
 100:         
 101:         if (obj == this) {
 102:             return true;
 103:         }
 104:         
 105:         if (!(obj instanceof HistogramType)) {
 106:             return false;
 107:         }
 108:         
 109:         HistogramType t = (HistogramType) obj;
 110:         if (!this.name.equals(t.name)) {
 111:             return false;
 112:         }
 113:         
 114:         return true;
 115:         
 116:     }
 117: 
 118:     /**
 119:      * Returns a hash code value for the object.
 120:      *
 121:      * @return The hashcode
 122:      */
 123:     public int hashCode() {
 124:         return this.name.hashCode();
 125:     }
 126: 
 127:     /**
 128:      * Ensures that serialization returns the unique instances.
 129:      * 
 130:      * @return The object.
 131:      * 
 132:      * @throws ObjectStreamException if there is a problem.
 133:      */
 134:     private Object readResolve() throws ObjectStreamException {
 135:         if (this.equals(HistogramType.FREQUENCY)) {
 136:             return HistogramType.FREQUENCY;
 137:         }
 138:         else if (this.equals(HistogramType.RELATIVE_FREQUENCY)) {
 139:             return HistogramType.RELATIVE_FREQUENCY;
 140:         }
 141:         else if (this.equals(HistogramType.SCALE_AREA_TO_1)) {
 142:             return HistogramType.SCALE_AREA_TO_1;
 143:         }
 144:         return null;
 145:     }
 146: 
 147: }
 148: