Source for org.jfree.chart.plot.DatasetRenderingOrder

   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:  * DatasetRenderingOrder.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:  * 02-May-2003 : Version 1 (DG);
  38:  * 02-Jun-2004 : Changed 'STANDARD' --> 'FORWARD' (DG);
  39:  * 21-Nov-2007 : Implemented hashCode() (DG);
  40:  *
  41:  */
  42: 
  43: package org.jfree.chart.plot;
  44: 
  45: import java.io.ObjectStreamException;
  46: import java.io.Serializable;
  47: 
  48: /**
  49:  * Defines the tokens that indicate the rendering order for datasets in a 
  50:  * {@link org.jfree.chart.plot.CategoryPlot} or an 
  51:  * {@link org.jfree.chart.plot.XYPlot}.
  52:  */
  53: public final class DatasetRenderingOrder implements Serializable {
  54: 
  55:     /** For serialization. */
  56:     private static final long serialVersionUID = -600593412366385072L;    
  57: 
  58:     /** 
  59:      * Render datasets in the order 0, 1, 2, ..., N-1, where N is the number 
  60:      * of datasets. 
  61:      */
  62:     public static final DatasetRenderingOrder FORWARD
  63:             = new DatasetRenderingOrder("DatasetRenderingOrder.FORWARD");
  64: 
  65:     /** 
  66:      * Render datasets in the order N-1, N-2, ..., 2, 1, 0, where N is the 
  67:      * number of datasets. 
  68:      */
  69:     public static final DatasetRenderingOrder REVERSE
  70:             = new DatasetRenderingOrder("DatasetRenderingOrder.REVERSE");
  71: 
  72:     /** The name. */
  73:     private String name;
  74: 
  75:     /**
  76:      * Private constructor.
  77:      *
  78:      * @param name  the name.
  79:      */
  80:     private DatasetRenderingOrder(String name) {
  81:         this.name = name;
  82:     }
  83: 
  84:     /**
  85:      * Returns a string representing the object.
  86:      *
  87:      * @return The string (never <code>null</code>).
  88:      */
  89:     public String toString() {
  90:         return this.name;
  91:     }
  92: 
  93:     /**
  94:      * Returns <code>true</code> if this object is equal to the specified 
  95:      * object, and <code>false</code> otherwise.
  96:      *
  97:      * @param obj  the object (<code>null</code> permitted).
  98:      *
  99:      * @return A boolean.
 100:      */
 101:     public boolean equals(Object obj) {
 102:         if (this == obj) {
 103:             return true;
 104:         }
 105:         if (!(obj instanceof DatasetRenderingOrder)) {
 106:             return false;
 107:         }
 108:         DatasetRenderingOrder order = (DatasetRenderingOrder) obj;
 109:         if (!this.name.equals(order.toString())) {
 110:             return false;
 111:         }
 112:         return true;
 113:     }
 114:     
 115:     /**
 116:      * Returns a hash code for this instance.
 117:      * 
 118:      * @return A hash code.
 119:      */
 120:     public int hashCode() {
 121:         return this.name.hashCode();
 122:     }
 123:     
 124:     /**
 125:      * Ensures that serialization returns the unique instances.
 126:      * 
 127:      * @return The object.
 128:      * 
 129:      * @throws ObjectStreamException if there is a problem.
 130:      */
 131:     private Object readResolve() throws ObjectStreamException {
 132:         if (this.equals(DatasetRenderingOrder.FORWARD)) {
 133:             return DatasetRenderingOrder.FORWARD;
 134:         }
 135:         else if (this.equals(DatasetRenderingOrder.REVERSE)) {
 136:             return DatasetRenderingOrder.REVERSE;
 137:         }      
 138:         return null;
 139:     }
 140: 
 141: }