001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-present, by David Gilbert and Contributors.
006 *
007 * Project Info:  http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022 * USA.
023 *
024 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 * ------------
028 * FlowKey.java
029 * ------------
030 * (C) Copyright 2022-present, by David Gilbert and Contributors.
031 *
032 * Original Author:  David Gilbert;
033 * Contributor(s):   -;
034 *
035 */
036
037package org.jfree.data.flow;
038
039import java.io.Serializable;
040import java.util.Objects;
041import org.jfree.chart.util.Args;
042import org.jfree.chart.util.PublicCloneable;
043
044/**
045 * A key that identifies a flow within a dataset.
046 * 
047 * @param <K> the type for the keys used to identify sources and destinations 
048 *     ({@code String} is a good default choice).
049 * 
050 * @since 1.5.3
051 */
052public class FlowKey<K extends Comparable<K>> implements PublicCloneable, Serializable  {
053
054    /** 
055     * The key for a flow property that, if defined (at the dataset level), 
056     * contains a {@code Boolean} value for the selection status of the flow.
057     */
058    public static final String SELECTED_PROPERTY_KEY = "selected";
059
060    /** The stage. */
061    private final int stage;
062    
063    /* The source node. */
064    private final K source;
065    
066    /* The destination node. */
067    private final K destination;
068    
069    /**
070     * Creates a new instance.
071     * 
072     * @param stage  the stage.
073     * @param source  the source identifier ({@code null} not permitted).
074     * @param destination  the destination identifier ({@code null} not permitted).
075     */
076    public FlowKey(int stage, K source, K destination) {
077        Args.nullNotPermitted(source, "source");
078        Args.nullNotPermitted(destination, "destination");
079        this.stage = stage;
080        this.source = source;
081        this.destination = destination;
082    }
083
084    /**
085     * Returns the stage number for the flow.
086     * 
087     * @return The stage number. 
088     */
089    public int getStage() {
090        return this.stage;
091    }
092    
093    /**
094     * Returns the source identifier.
095     * 
096     * @return The source identifier (never {@code null}). 
097     */
098    public K getSource() {
099        return source;
100    }
101
102    /**
103     * Returns the destination identifier.
104     * 
105     * @return The destination identifier (never {@code null}). 
106     */
107    public K getDestination() {
108        return destination;
109    }
110
111    /**
112     * Returns a string representation of this instance, primarily for 
113     * debugging purposes.
114     * 
115     * @return A string. 
116     */
117    @Override
118    public String toString() {
119        return "[FlowKey: " + this.stage + ", " + this.source + " -> " + this.destination + "]";
120    }
121    
122    /**
123     * Tests this instance for equality with an arbitrary object.
124     * 
125     * @param obj  the object ({@code null} permitted).
126     * 
127     * @return A boolean. 
128     */
129    @Override
130    public boolean equals(Object obj) {
131        if (this == obj) {
132            return true;
133        }
134        if (obj == null) {
135            return false;
136        }
137        if (getClass() != obj.getClass()) {
138            return false;
139        }
140        final FlowKey<?> other = (FlowKey<?>) obj;
141        if (this.stage != other.stage) {
142            return false;
143        }
144        if (!Objects.equals(this.source, other.source)) {
145            return false;
146        }
147        if (!Objects.equals(this.destination, other.destination)) {
148            return false;
149        }
150        return true;
151    }
152    
153    /**
154     * Returns a hashcode for this instance.
155     * 
156     * @return A hashcode.
157     */
158    @Override
159    public int hashCode() {
160        int hash = 5;
161        hash = 67 * hash + this.stage;
162        hash = 67 * hash + Objects.hashCode(this.source);
163        hash = 67 * hash + Objects.hashCode(this.destination);
164        return hash;
165    }
166
167    @Override
168    public Object clone() throws CloneNotSupportedException {
169        return super.clone();
170    }    
171
172}
173