001 package edu.nrao.sss.model.project.scan;
002
003 import java.util.ArrayList;
004 import java.util.EnumSet;
005 import java.util.List;
006
007 import edu.nrao.sss.util.EnumerationUtility;
008
009 /**
010 * An enumeration of the different kinds of time associated with a
011 * {@link Scan}. An observer may specify either a <i>duration</i> or a
012 * <i>point in time</i> for a scan. If duration is chosen, the observer
013 * may then choose either a total duration or the amount of time to
014 * spend on-source.
015 * If time is chosen, the observer may then
016 * choose either a start or stop time. For both durations and times
017 * a choice must also be made between expressing time in sidereal unit
018 * or standard units.
019 * <p>
020 * <b>Version Info:</b>
021 * <table style="margin-left:2em">
022 * <tr><td>$Revision: 2142 $</td></tr>
023 * <tr><td>$Date: 2009-03-30 13:29:56 -0600 (Mon, 30 Mar 2009) $</td></tr>
024 * <tr><td>$Author: btruitt $</td></tr>
025 * </table></p>
026 *
027 * @author David M. Harland
028 * @since 2006-07-14
029 */
030 public enum ScanTimeType
031 {
032 /**
033 * The amount of time spent observing a source, in sidereal units.
034 */
035 ON_SOURCE_SIDEREAL(T.ON_SOURCE, T.SIDEREAL, "On Source (LST)"),
036
037 /**
038 * The total amount of time spent on a scan, in sidereal units.
039 * This time includes both time spent on the source
040 * and time spent moving the telescope from one source
041 * to another and time spent configuring the hardware.
042 */
043 DURATION_SIDEREAL(T.TOTAL_DUR, T.SIDEREAL, "Duration (LST)"),
044
045 /**
046 * The local sidereal time at which a scan begins.
047 */
048 START_LST(T.START, T.SIDEREAL, "Start Time (LST)"),
049
050 /**
051 * The local sidereal time at which a scan concludes.
052 */
053 STOP_LST(T.STOP, T.SIDEREAL, "Stop Time (LST)"),
054
055 /**
056 * The amount of time spent observing a source, in SI units.
057 */
058 ON_SOURCE_UT(T.ON_SOURCE, T.UT, "On Source (UT)"),
059
060 /**
061 * The total amount of time spent on a scan, in SI units.
062 * This time includes both time spent on the source
063 * and time spent moving the telescope from one source
064 * to another and time spent configuring the hardware.
065 */
066 DURATION_UT(T.TOTAL_DUR, T.UT, "Duration (UT)"),
067
068 /**
069 * The date and time at which a scan begins.
070 * <p>
071 * The date/time is expressed in conventional units.
072 * Though the "UT" suffix may seem to imply that the Greenwich
073 * time zone be used, that is not the case. Any time zone may
074 * be used; the time merely needs to be in SI units, not
075 * sidereal units.</p>
076 */
077 START_UT(T.START, T.UT, "Start Time (UT)"),
078
079 /**
080 * The date and time at which a scan concludes.
081 * <p>
082 * The date/time is expressed in conventional units.
083 * Though the "UT" suffix may seem to imply that the Greenwich
084 * time zone be used, that is not the case. Any time zone may
085 * be used; the time merely needs to be in SI units, not
086 * sidereal units.</p>
087 */
088 STOP_UT(T.STOP, T.UT, "Stop Time (UT)");
089
090 private static interface T
091 {
092 public int START = 1;
093 public int STOP = 2;
094 public int ON_SOURCE = 3;
095 public int TOTAL_DUR = 4;
096
097 public boolean SIDEREAL = true;
098 public boolean UT = false;
099 }
100
101 private String displayText;
102
103 private boolean isStart;
104 private boolean isStop;
105 private boolean isOnSource;
106 private boolean isTotalDuration;
107 private boolean isSidereal;
108
109 private ScanTimeType(int timeType, boolean isStellar, String display)
110 {
111 displayText = display;
112
113 isSidereal = isStellar;
114
115 switch (timeType)
116 {
117 case T.START:
118 isStart = true;
119 isStop = isOnSource = isTotalDuration = false;
120 break;
121
122 case T.STOP:
123 isStop = true;
124 isStart = isOnSource = isTotalDuration = false;
125 break;
126
127 case T.ON_SOURCE:
128 isOnSource = true;
129 isStart = isStop = isTotalDuration = false;
130 break;
131
132 case T.TOTAL_DUR:
133 isTotalDuration = true;
134 isStart = isStop = isOnSource = false;
135 break;
136
137 default:
138 throw new RuntimeException("PROGRAMMER ERROR: Unknown timeType of '" +
139 timeType +"'.");
140 }
141 }
142
143 /**
144 * Returns the time type to use as a default.
145 * @return a default scan time type.
146 */
147 public static ScanTimeType getDefault()
148 {
149 return ON_SOURCE_SIDEREAL;
150 }
151
152 /**
153 * Returns <i>true</i> if this time type is a duration
154 * (as opposed to a point in time).
155 *
156 * @return <i>true</i> if this time type is a duration.
157 */
158 public boolean isDuration() { return isOnSource || isTotalDuration; }
159
160 /**
161 * Returns <i>true</i> if this time type is a point in time
162 * (as opposed to a duration).
163 *
164 * @return <i>true</i> if this time type is a point in time.
165 */
166 public boolean isPointInTime() { return isStart || isStop; }
167
168 /**
169 * Returns <i>true</i> if this time type is a time-on-source duration.
170 * @return <i>true</i> if this time type is a time-on-source duration.
171 */
172 public boolean isOnSourceDuration() { return isOnSource; }
173
174 /**
175 * Returns <i>true</i> if this time type is a total duration.
176 * @return <i>true</i> if this time type is a total duration.
177 */
178 public boolean isTotalDuration() { return isTotalDuration; }
179
180 /**
181 * Returns <i>true</i> if this time type is a start time.
182 * @return <i>true</i> if this time type is a start time.
183 */
184 public boolean isStartTime() { return isStart; }
185
186 /**
187 * Returns <i>true</i> if this time type is a stop time.
188 * @return <i>true</i> if this time type is a stop time.
189 */
190 public boolean isStopTime() { return isStop; }
191
192 /**
193 * Returns <i>true</i> if this time type is expressed in SI units.
194 * @return <i>true</i> if this time type is expressed in SI units.
195 */
196 public boolean isUniversalTime() { return !isSidereal; }
197
198 /**
199 * Returns <i>true</i> if this time type is expressed in sidereal units.
200 * @return <i>true</i> if this time type is expressed in sidereal units.
201 */
202 public boolean isSiderealTime() { return isSidereal; }
203
204 /**
205 * Returns a text representation of this enumeration constant.
206 * @return a text representation of this enumeration constant.
207 */
208 @Override
209 public String toString() { return displayText; }
210
211 /**
212 * Returns the scan time type represented by {@code text}.
213 * <p>
214 * For details about the transformation, see
215 * {@link EnumerationUtility#enumFromString(Class, String)}.</p>
216 *
217 * @param text a text representation of a scan time type.
218 *
219 * @return the scan time type represented by {@code text}.
220 */
221 public static ScanTimeType fromString(String text)
222 {
223 return EnumerationUtility.getSharedInstance()
224 .enumFromString(ScanTimeType.class, text);
225 }
226
227 //============================================================================
228 // SUBSETS OF THIS ENUMERATION
229 //============================================================================
230
231 private static final EnumSet<ScanTimeType> SIDEREAL_ELEMENTS =
232 EnumSet.of(ON_SOURCE_SIDEREAL, DURATION_SIDEREAL, START_LST, STOP_LST);
233
234 private static final EnumSet<ScanTimeType> UT_ELEMENTS =
235 EnumSet.of(ON_SOURCE_UT, DURATION_UT, START_UT, STOP_UT);
236
237 /**
238 * Returns the elements of this enumeration that are based on sidereal time.
239 * The returned list is not referenced by this class and may therefore be
240 * safely manipulated by clients.
241 *
242 * @return
243 * the elements of this enumeration that are based on sidereal time.
244 */
245 public static List<ScanTimeType> siderealSubset()
246 {
247 return new ArrayList<ScanTimeType>(SIDEREAL_ELEMENTS);
248 }
249
250 /**
251 * Returns the elements of this enumeration that are based on universal time.
252 * The returned list is not referenced by this class and may therefore be
253 * safely manipulated by clients.
254 *
255 * @return
256 * the elements of this enumeration that are based on universal time.
257 */
258 public static List<ScanTimeType> utSubset()
259 {
260 return new ArrayList<ScanTimeType>(UT_ELEMENTS);
261 }
262 }