001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2014, 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 * [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 * CompassFormat.java
029 * ------------------
030 * (C) Copyright 2003-2014, by Sylvain Vieujot and Contributors.
031 *
032 * Original Author:  Sylvain Vieujot;
033 * Contributor(s):   David Gilbert (for Object Refinery Limited);
034 *                   Simon Legner (GitHub #298);
035 *
036 * Changes
037 * -------
038 * 18-Feb-2004 : Version 1 contributed by Sylvain Vieujot (DG);
039 * 04-Feb-2014 : Make direction strings user-definable (SL);
040 * 
041 */
042
043package org.jfree.chart.axis;
044
045import java.text.FieldPosition;
046import java.text.NumberFormat;
047import java.text.ParsePosition;
048import org.jfree.chart.util.ParamChecks;
049
050/**
051 * A formatter that displays numbers as directions.
052 */
053public class CompassFormat extends NumberFormat {
054
055    /** The directions. */
056    public final String[] directions;
057
058    /**
059     * Creates a new formatter using English identifiers.
060     */
061    public CompassFormat() {
062        this("N", "E", "S", "W");
063    }
064
065    /**
066     * Creates a new formatter using the specified identifiers for
067     * the base wind directions.
068     * 
069     * @param n  the code for NORTH.
070     * @param e  the code for EAST.
071     * @param s  the code for SOUTH.
072     * @param w  the code for WEST.
073     * 
074     * @since 1.0.18
075     */
076    public CompassFormat(String n, String e, String s, String w) {
077        this(new String[] {
078            n, n + n + e, n + e, e + n + e, e, e + s + e, s + e, s + s + e, s,
079            s + s + w, s + w, w + s + w, w, w + n + w, n + w, n + n + w
080        });
081    }
082
083    /**
084     * Creates a new formatter using the specified identifiers.
085     * 
086     * @param directions  an array containing 16 strings representing
087     *     the directions of a compass.
088     * 
089     * @since 1.0.18
090     */
091    public CompassFormat(String[] directions) {
092        super();
093        ParamChecks.nullNotPermitted(directions, "directions");
094        if (directions.length != 16) {
095            throw new IllegalArgumentException("The 'directions' array must "
096                    + "contain exactly 16 elements");
097        }
098        this.directions = directions;
099    }
100
101    /**
102     * Returns a string representing the direction.
103     *
104     * @param direction  the direction.
105     *
106     * @return A string.
107     */
108    public String getDirectionCode(double direction) {
109        direction = direction % 360;
110        if (direction < 0.0) {
111            direction = direction + 360.0;
112        }
113        int index = ((int) Math.floor(direction / 11.25) + 1) / 2;
114        return directions[index];
115    }
116
117    /**
118     * Formats a number into the specified string buffer.
119     *
120     * @param number  the number to format.
121     * @param toAppendTo  the string buffer.
122     * @param pos  the field position (ignored here).
123     *
124     * @return The string buffer.
125     */
126    @Override
127    public StringBuffer format(double number, StringBuffer toAppendTo,
128            FieldPosition pos) {
129        return toAppendTo.append(getDirectionCode(number));
130    }
131
132    /**
133     * Formats a number into the specified string buffer.
134     *
135     * @param number  the number to format.
136     * @param toAppendTo  the string buffer.
137     * @param pos  the field position (ignored here).
138     *
139     * @return The string buffer.
140     */
141    @Override
142    public StringBuffer format(long number, StringBuffer toAppendTo,
143            FieldPosition pos) {
144        return toAppendTo.append(getDirectionCode(number));
145    }
146
147    /**
148     * This method returns <code>null</code> for all inputs.  This class cannot
149     * be used for parsing.
150     *
151     * @param source  the source string.
152     * @param parsePosition  the parse position.
153     *
154     * @return <code>null</code>.
155     */
156    @Override
157    public Number parse(String source, ParsePosition parsePosition) {
158        return null;
159    }
160
161}