www.pudn.com > jfreechart-0.9.12.zip > CategoryAnchor.java

/* ====================================== 
 * JFreeChart : a free Java chart library 
 * ====================================== 
 * 
 * Project Info:  http://www.jfree.org/jfreechart/index.html 
 * Project Lead:  David Gilbert (david.gilbert@object-refinery.com); 
 * 
 * (C) Copyright 2000-2003, by Object Refinery Limited and Contributors. 
 * 
 * This library is free software; you can redistribute it and/or modify it under the terms 
 * of the GNU Lesser General Public License as published by the Free Software Foundation; 
 * either version 2.1 of the License, or (at your option) any later version. 
 * 
 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; 
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
 * See the GNU Lesser General Public License for more details. 
 * 
 * You should have received a copy of the GNU Lesser General Public License along with this 
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, 
 * Boston, MA 02111-1307, USA. 
 * 
 * ------------------- 
 * CategoryAnchor.java 
 * ------------------- 
 * (C) Copyright 2003 by Object Refinery Limited. 
 * 
 * Original Author:  David Gilbert (for Object Refinery Limited); 
 * Contributor(s):   -; 
 * 
 * $Id: CategoryAnchor.java,v 1.2 2003/08/20 11:40:38 mungady Exp $ 
 * 
 * Changes: 
 * -------- 
 * 04-Jul-2003 : Version 1 (DG); 
 * 
 */ 
 
package org.jfree.chart.axis; 
 
import java.io.ObjectStreamException; 
import java.io.Serializable; 
 
/** 
 * Used to indicate one of three positions within a category: START,  
 * MIDDLE and END. 
 * 
 * @author David Gilbert 
 */ 
public final class CategoryAnchor implements Serializable { 
 
    /** Start of period. */ 
    public static final CategoryAnchor START = new CategoryAnchor("CategoryAnchor.START"); 
 
    /** Middle of period. */ 
    public static final CategoryAnchor MIDDLE = new CategoryAnchor("CategoryAnchor.MIDDLE"); 
 
    /** End of period. */ 
    public static final CategoryAnchor END = new CategoryAnchor("CategoryAnchor.END"); 
 
    /** The name. */ 
    private String name; 
 
    /** 
     * Private constructor. 
     * 
     * @param name  the name. 
     */ 
    private CategoryAnchor(String name) { 
        this.name = name; 
    } 
 
    /** 
     * Returns a string representing the object. 
     * 
     * @return The string. 
     */ 
    public String toString() { 
        return this.name; 
    } 
 
    /** 
     * Returns true if this object is equal to the specified object, and 
     * false otherwise. 
     * 
     * @param o  the other object. 
     * 
     * @return A boolean. 
     */ 
    public boolean equals(Object o) { 
 
        if (this == o) { 
            return true; 
        } 
        if (!(o instanceof CategoryAnchor)) { 
            return false; 
        } 
 
        final CategoryAnchor position = (CategoryAnchor) o; 
        if (!this.name.equals(position.toString())) { 
            return false; 
        } 
 
        return true; 
 
    } 
     
    /** 
     * Ensures that serialization returns the unique instances. 
     *  
     * @return The object. 
     *  
     * @throws ObjectStreamException if there is a problem. 
     */ 
    private Object readResolve() throws ObjectStreamException { 
        if (this.equals(CategoryAnchor.START)) { 
            return CategoryAnchor.START; 
        } 
        else if (this.equals(CategoryAnchor.MIDDLE)) { 
            return CategoryAnchor.MIDDLE; 
        }     
        else if (this.equals(CategoryAnchor.END)) { 
            return CategoryAnchor.END; 
        }     
        return null; 
    } 
 
}