001    /* ===========================================================
002     * JFreeChart : a free chart library for the Java(tm) platform
003     * ===========================================================
004     *
005     * (C) Copyright 2000-2007, by Object Refinery Limited 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     * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
025     * in the United States and other countries.]
026     *
027     * -------------
028     * Timeline.java
029     * -------------
030     * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
031     *
032     * Original Author:  Bill Kelemen;
033     * Contributor(s):   David Gilbert (for Object Refinery Limited);
034     *
035     * $Id: Timeline.java,v 1.2.2.2 2007/02/02 14:32:42 mungady Exp $
036     *
037     * Changes
038     * -------
039     * 23-May-2003 : Version 1 (BK);
040     * 09-Sep-2003 : Changed some method and parameter names (DG);
041     * 02-Feb-2007 : Removed author tags all over JFreeChart sources (DG);
042     * 
043     */
044    
045    package org.jfree.chart.axis;
046    
047    import java.util.Date;
048    
049    /**
050     * An interface that defines the contract for a Timeline.
051     * <P>
052     * A Timeline will present a series of values to be used for an axis. Each
053     * Timeline must provide transformation methods between domain values and
054     * timeline values. In theory many transformations are possible. This interface
055     * has been implemented completely in 
056     * {@link org.jfree.chart.axis.SegmentedTimeline}.
057     * <P>
058     * A timeline can be used as parameter to a 
059     * {@link org.jfree.chart.axis.DateAxis} to define the values that this axis 
060     * supports. As an example, the {@link org.jfree.chart.axis.SegmentedTimeline} 
061     * implements a timeline formed by segments of equal length (ex. days, hours, 
062     * minutes) where some segments can be included in the timeline and others 
063     * excluded. Therefore timelines like "working days" or "working hours" can be 
064     * created where non-working days or non-working hours respectively can be 
065     * removed from the timeline, and therefore from the axis. This creates a smooth
066     * plot with equal separation between all included segments.
067     * <P>
068     * Because Timelines were created mainly for Date related axis, values are
069     * represented as longs instead of doubles. In this case, the domain value is
070     * just the number of milliseconds since January 1, 1970, 00:00:00 GMT as 
071     * defined by the getTime() method of {@link java.util.Date}.
072     *
073     * @see org.jfree.chart.axis.SegmentedTimeline
074     * @see org.jfree.chart.axis.DateAxis
075     */
076    public interface Timeline {
077    
078        /**
079         * Translates a millisecond (as defined by java.util.Date) into an index 
080         * along this timeline.
081         *
082         * @param millisecond  the millisecond.
083         * 
084         * @return A timeline value.
085         */
086        long toTimelineValue(long millisecond);
087    
088        /**
089         * Translates a date into a value on this timeline.
090         *
091         * @param date  the date.
092         * 
093         * @return A timeline value
094         */
095        long toTimelineValue(Date date);
096    
097        /**
098         * Translates a value relative to this timeline into a domain value. The 
099         * domain value obtained by this method is not always the same domain value 
100         * that could have been supplied to 
101         * translateDomainValueToTimelineValue(domainValue).
102         * This is because the original tranformation may not be complete 
103         * reversable.
104         *
105         * @see org.jfree.chart.axis.SegmentedTimeline
106         *
107         * @param timelineValue  a timeline value.
108         * 
109         * @return A domain value.
110         */
111        long toMillisecond(long timelineValue);
112    
113        /**
114         * Returns <code>true</code> if a value is contained in the timeline values.
115         *
116         * @param millisecond  the millisecond.
117         * 
118         * @return <code>true</code> if value is contained in the timeline and 
119         *         <code>false</code> otherwise.
120         */
121        boolean containsDomainValue(long millisecond);
122    
123        /**
124         * Returns <code>true</code> if a date is contained in the timeline values.
125         *
126         * @param date  the date to verify.
127         * 
128         * @return <code>true</code> if value is contained in the timeline and 
129         *         <code>false</code>  otherwise.
130         */
131        boolean containsDomainValue(Date date);
132    
133        /**
134         * Returns <code>true</code> if a range of values are contained in the 
135         * timeline.
136         *
137         * @param fromMillisecond  the start of the range to verify.
138         * @param toMillisecond  the end of the range to verify.
139         * 
140         * @return <code>true</code> if the range is contained in the timeline or 
141         *         <code>false</code> otherwise
142         */
143        boolean containsDomainRange(long fromMillisecond, long toMillisecond);
144    
145        /**
146         * Returns <code>true</code> if a range of dates are contained in the 
147         * timeline.
148         *
149         * @param fromDate  the start of the range to verify.
150         * @param toDate  the end of the range to verify.
151         * 
152         * @return <code>true</code> if the range is contained in the timeline or 
153         *         <code>false</code> otherwise
154         */
155        boolean containsDomainRange(Date fromDate, Date toDate);
156    
157    }