001 package edu.nrao.sss.astronomy;
002
003 import edu.nrao.sss.measure.ArcUnits;
004 import edu.nrao.sss.measure.Latitude;
005 import edu.nrao.sss.measure.Longitude;
006 import edu.nrao.sss.util.EnumerationUtility;
007 import edu.nrao.sss.util.StringUtil;
008
009 /**
010 * An enumeration of coordinate systems commonly used in astronomy.
011 * <p>
012 * <b>Version Info:</b>
013 * <table style="margin-left:2em">
014 * <tr><td>$Revision: 952 $</td></tr>
015 * <tr><td>$Date: 2007-10-05 10:25:17 -0600 (Fri, 05 Oct 2007) $</td></tr>
016 * <tr><td>$Author: dharland $</td></tr>
017 * </table></p>
018 *
019 * @author David M. Harland
020 * @since 2006-07-18
021 */
022 public enum CelestialCoordinateSystem
023 {
024 //NOTE: the fromString method relies on all latitude and longitude
025 // names and abbreviations being unique. If you must violate the
026 // uniqueness, you will have to recode fromString so that it does
027 // not create enumeration elements from the lat/lon name/abbr.
028 // Doing so may impact applications that rely on the current behavior.
029 /**
030 * A spherical system based on the projection of the earth's equator onto
031 * the celestial sphere.
032 */
033 EQUATORIAL("Right Ascension", "Declination", "RA", "Dec")
034 {
035 @Override
036 public String latitudeToString(Latitude latitude,
037 int minFracDigits, int maxFracDigits)
038 {
039 return latitude == null ?
040 "NULL" : latitude.toStringDms(minFracDigits, maxFracDigits);
041 }
042
043 @Override
044 public String longitudeToString(Longitude longitude,
045 int minFracDigits, int maxFracDigits)
046 {
047 return longitude == null ?
048 "NULL" : longitude.toStringHms(minFracDigits, maxFracDigits);
049 }
050 },
051
052 /**
053 * A spherical system based on the projection of the observer's horizon onto
054 * the celestial sphere.
055 */
056 HORIZONTAL("Azimuth", "Elevation", "Az", "El"),
057
058 /**
059 * A spherical system based on the center of the sun and the central plane
060 * of our galaxy.
061 */
062 GALACTIC("Galactic Longitude", "Galactic Latitude", "GLon", "GLat"),
063
064 /**
065 * A spherical system based on the center of the earth and the earth's
066 * orbit around the sun.
067 */
068 ECLIPTIC("Ecliptic Longitude", "Ecliptic Latitude", "ELon", "ELat");
069
070 //SUPERGALACTIC
071
072 private String nameOfLongitude;
073 private String nameOfLatitude;
074 private String abbrOfLongitude;
075 private String abbrOfLatitude;
076
077 private CelestialCoordinateSystem(String longName, String latName,
078 String longAbbr, String latAbbr)
079 {
080 nameOfLongitude = longName;
081 nameOfLatitude = latName;
082 abbrOfLongitude = longAbbr;
083 abbrOfLatitude = latAbbr;
084 }
085
086 /**
087 * Returns the name commonly used for the longitude component of this
088 * system.
089 * @return the name of the longitude component of this system.
090 */
091 public String getNameOfLongitude() { return nameOfLongitude; }
092
093 /**
094 * Returns the name commonly used for the latitude component of this
095 * system.
096 * @return the name of the latitude component of this system.
097 */
098 public String getNameOfLatitude() { return nameOfLatitude; }
099
100 /**
101 * Returns the abbreviation commonly used for the longitude component of this
102 * system.
103 * @return an abbreviation for the longitude component of this system.
104 */
105 public String getAbbreviationForLongitude() { return abbrOfLongitude; }
106
107 /**
108 * Returns the abbreviation commonly used for the latitude component of this
109 * system.
110 * @return an abbreviation for the latitude component of this system.
111 */
112 public String getAbbreviationForLatitude() { return abbrOfLatitude; }
113
114 /**
115 * Returns a text representation of {@code latitude} that is appropriate
116 * for this coordinate system. Note that this might <i>not</i> be the
117 * same text returned by {@code latitude.toString()}.
118 * @param latitude the latitude to be represented as text.
119 * @param minFracDigits the minimum number of places after the decimal point.
120 * @param maxFracDigits the maximum number of places after the decimal point.
121 * @return a text representation of {@code latitude}.
122 */
123 public String latitudeToString(Latitude latitude,
124 int minFracDigits, int maxFracDigits)
125 {
126 String text = "NULL";
127
128 if (latitude != null)
129 {
130 text = latitude.clone().convertTo(ArcUnits.DEGREE)
131 .toString(minFracDigits, maxFracDigits);
132 }
133
134 return text;
135 }
136
137 /**
138 * Returns a text representation of {@code longitude} that is appropriate
139 * for this coordinate system. Note that this might <i>not</i> be the
140 * same text returned by {@code longitude.toString()}.
141 * @param longitude the longitude to be represented as text.
142 * @param minFracDigits the minimum number of places after the decimal point.
143 * @param maxFracDigits the maximum number of places after the decimal point.
144 * @return a text representation of {@code longitude}.
145 */
146 public String longitudeToString(Longitude longitude,
147 int minFracDigits, int maxFracDigits)
148 {
149 String text = "NULL";
150
151 if (longitude != null)
152 {
153 text = longitude.clone().convertTo(ArcUnits.DEGREE)
154 .toString(minFracDigits, maxFracDigits);
155 }
156
157 return text;
158 }
159
160 /**
161 * Returns a default coordinate system.
162 * @return a default coordinate system.
163 */
164 public static CelestialCoordinateSystem getDefault()
165 {
166 return EQUATORIAL;
167 }
168
169 /**
170 * Returns a text representation of this enumeration constant.
171 * @return a text representation of this enumeration constant.
172 */
173 public String toString()
174 {
175 return EnumerationUtility.getSharedInstance().enumToString(this);
176 }
177
178 /**
179 * Returns the celestial coordinate system represented by {@code text}.
180 * <p>
181 * For details about the transformation, see
182 * {@link EnumerationUtility#enumFromString(Class, String)}.</p>
183 *
184 * @param text a text representation of a celestial coordinate system.
185 *
186 * @return the celestial coordinate system represented by {@code text}.
187 */
188 public static CelestialCoordinateSystem fromString(String text)
189 {
190 CelestialCoordinateSystem result =
191 EnumerationUtility.getSharedInstance()
192 .enumFromString(CelestialCoordinateSystem.class, text);
193
194 if (result == null)
195 {
196 text = StringUtil.getInstance().normalizeString(text);
197
198 for (CelestialCoordinateSystem ccs : CelestialCoordinateSystem.values())
199 {
200 if (ccs.nameOfLatitude.equalsIgnoreCase(text) ||
201 ccs.abbrOfLatitude.equalsIgnoreCase(text) ||
202 ccs.nameOfLongitude.equalsIgnoreCase(text) ||
203 ccs.abbrOfLongitude.equalsIgnoreCase(text))
204 {
205 result = ccs;
206 break;
207 }
208 }
209 }
210
211 return result;
212 }
213
214 //Quick & dirty testing
215 /*
216 public static void main(String[] args) throws Exception
217 {
218 Latitude lat = new Latitude(87.654);
219 Longitude lon = new Longitude(123.456);
220
221 System.out.println();
222 System.out.print("Galactic: ");
223 System.out.print(" Lon = ");
224 System.out.print(CelestialCoordinateSystem.GALACTIC.longitudeToString(lon, 3, 3));
225 System.out.print(", Lat = ");
226 System.out.print(CelestialCoordinateSystem.GALACTIC.latitudeToString(lat, 3, 3));
227 System.out.println();
228
229 System.out.println();
230 System.out.print("Equatorial: ");
231 System.out.print(" Lon = ");
232 System.out.print(CelestialCoordinateSystem.EQUATORIAL.longitudeToString(lon, 3, 3));
233 System.out.print(", Lat = ");
234 System.out.print(CelestialCoordinateSystem.EQUATORIAL.latitudeToString(lat, 3, 3));
235 System.out.println();
236
237 lat = new Latitude(-25.0, ArcUnits.PERCENT);
238 lon = new Longitude(3.14159/4.0, ArcUnits.RADIAN);
239
240 System.out.println();
241 System.out.print("Galactic: ");
242 System.out.print(" Lon = ");
243 System.out.print(CelestialCoordinateSystem.GALACTIC.longitudeToString(lon, 3, 3));
244 System.out.print(", Lat = ");
245 System.out.print(CelestialCoordinateSystem.GALACTIC.latitudeToString(lat, 3, 3));
246 System.out.println();
247 }
248 */
249 }