Added a link from Span to Transition in TimeSpanMap.

src/main/java/org/orekit/utils/TimeSpanMap.java

@@ -268,18 +268,23 @@ public class TimeSpanMap<T> {
      * @since 9.3
      */
     public Span<T> getSpan(final AbsoluteDate date) {
+
+        if (data.size() == 1) {
+            final Transition<T> single = data.first();
+            if (single.getBefore() == single.getAfter()) {
+                // the single entry was a dummy one, without a real transition
+                return new Span<>(single.getBefore(), null, null);
+            }
+        }
+
         final Transition<T> previous = data.floor(new Transition<>(date, null, null));
         if (previous == null) {
             // there are no transition before the specified date
             // return the first valid entry
-            return new Span<>(data.first().getBefore(),
-                              AbsoluteDate.PAST_INFINITY,
-                              data.first().getDate());
+            return new Span<>(data.first().getBefore(), null, data.first());
         } else {
             final Transition<T> next = data.higher(previous);
-            return new Span<>(previous.getAfter(),
-                              previous.getDate(),
-                              next == null ? AbsoluteDate.FUTURE_INFINITY : next.getDate());
+            return new Span<>(previous.getAfter(), previous, next == null ? null : next);
         }
     }
 
@@ -426,18 +431,18 @@ public class TimeSpanMap<T> {
         /** Valid data. */
         private final S data;
 
-        /** Start of validity for the data. */
-        private final AbsoluteDate start;
+        /** Start of validity for the data (null if span extends to past infinity). */
+        private Transition<S> start;
 
-        /** End of validity for the data. */
-        private final AbsoluteDate end;
+        /** End of validity for the data (null if span extends to future infinity). */
+        private Transition<S> end;
 
         /** Simple constructor.
          * @param data valid data
-         * @param start start of validity for the data
-         * @param end end of validity for the data
+         * @param start transition at start of validity for the data (null if span extends to past infinity)
+         * @param end transition at end of validity for the data (null if span extends to future infinity)
          */
-        private Span(final S data, final AbsoluteDate start, final AbsoluteDate end) {
+        private Span(final S data, final Transition<S> start, final Transition<S> end) {
             this.data  = data;
             this.start = start;
             this.end   = end;
@@ -451,16 +456,38 @@ public class TimeSpanMap<T> {
         }
 
         /** Get the start of this time span.
-         * @return start of this time span
+         * @return start of this time span (will be {@link AbsoluteDate#PAST_INFINITY}
+         * if {@link #getStartTransition() returns null)
+         * @see #getStartTransition()
          */
         public AbsoluteDate getStart() {
+            return start == null ? AbsoluteDate.PAST_INFINITY : start.getDate();
+        }
+
+        /** Get the transition at start of this time span.
+         * @return transition at start of this time span (null if span extends to past infinity)
+         * @see #getStart()
+         * @since 11.1
+         */
+        public Transition<S> getStartTransition() {
             return start;
         }
 
         /** Get the end of this time span.
-         * @return end of this time span
+         * @return end of this time span (will be {@link AbsoluteDate#FUTURE_INFINITY}
+         * if {@link #getEndTransition() returns null)
+         * @see #getEndTransition()
          */
         public AbsoluteDate getEnd() {
+            return end == null ? AbsoluteDate.FUTURE_INFINITY : end.getDate();
+        }
+
+        /** Get the transition at end of this time span.
+         * @return transition at end of this time span (null if span extends to future infinity)
+         * @see #getEnd()
+         * @since 11.1
+         */
+        public Transition<S> getEndTransition() {
             return end;
         }
 

src/test/java/org/orekit/utils/TimeSpanMapTest.java

@@ -173,7 +173,7 @@ public class TimeSpanMapTest {
     @Test
     public void testExtractRangeInfinity() {
         final AbsoluteDate ref = AbsoluteDate.J2000_EPOCH;
-        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));        
+        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));
         map.addValidAfter(Integer.valueOf(10), ref.shiftedBy(10.0), false);
         map.addValidAfter(Integer.valueOf( 3), ref.shiftedBy( 2.0), false);
         map.addValidAfter(Integer.valueOf( 9), ref.shiftedBy( 5.0), false);
@@ -186,7 +186,7 @@ public class TimeSpanMapTest {
     @Test
     public void testExtractRangeSingleEntry() {
         final AbsoluteDate ref = AbsoluteDate.J2000_EPOCH;
-        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));        
+        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));
         map.addValidAfter(Integer.valueOf(10), ref.shiftedBy(10.0), false);
         map.addValidAfter(Integer.valueOf( 3), ref.shiftedBy( 2.0), false);
         map.addValidAfter(Integer.valueOf( 9), ref.shiftedBy( 5.0), false);
@@ -201,7 +201,7 @@ public class TimeSpanMapTest {
     @Test
     public void testExtractFromPastInfinity() {
         final AbsoluteDate ref = AbsoluteDate.J2000_EPOCH;
-        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));        
+        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));
         map.addValidAfter(Integer.valueOf(10), ref.shiftedBy(10.0), false);
         map.addValidAfter(Integer.valueOf( 3), ref.shiftedBy( 2.0), false);
         map.addValidAfter(Integer.valueOf( 9), ref.shiftedBy( 5.0), false);
@@ -224,7 +224,7 @@ public class TimeSpanMapTest {
     @Test
     public void testExtractToFutureInfinity() {
         final AbsoluteDate ref = AbsoluteDate.J2000_EPOCH;
-        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));        
+        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));
         map.addValidAfter(Integer.valueOf(10), ref.shiftedBy(10.0), false);
         map.addValidAfter(Integer.valueOf( 3), ref.shiftedBy( 2.0), false);
         map.addValidAfter(Integer.valueOf( 9), ref.shiftedBy( 5.0), false);
@@ -245,7 +245,7 @@ public class TimeSpanMapTest {
     @Test
     public void testExtractIntermediate() {
         final AbsoluteDate ref = AbsoluteDate.J2000_EPOCH;
-        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));        
+        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));
         map.addValidAfter(Integer.valueOf(10), ref.shiftedBy(10.0), false);
         map.addValidAfter(Integer.valueOf( 3), ref.shiftedBy( 2.0), false);
         map.addValidAfter(Integer.valueOf( 9), ref.shiftedBy( 5.0), false);
@@ -261,6 +261,54 @@ public class TimeSpanMapTest {
         Assert.assertEquals( 5, range.get(ref.shiftedBy(999.9)).intValue());
     }
 
+    @Test
+    public void testSpanToTransitionLinkEmpty() {
+        TimeSpanMap.Span<Integer> span = new TimeSpanMap<>(1).getSpan(AbsoluteDate.ARBITRARY_EPOCH);
+        Assert.assertEquals(1, span.getData().intValue());
+        Assert.assertSame(AbsoluteDate.PAST_INFINITY, span.getStart());
+        Assert.assertNull(span.getStartTransition());
+        Assert.assertSame(AbsoluteDate.FUTURE_INFINITY, span.getEnd());
+        Assert.assertNull(span.getEndTransition());
+    }
+
+    @Test
+    public void testSpanToTransitionLink() {
+        final AbsoluteDate ref = AbsoluteDate.ARBITRARY_EPOCH;
+        TimeSpanMap<Integer> map = new TimeSpanMap<>(Integer.valueOf(0));
+        map.addValidAfter(Integer.valueOf(10), ref.shiftedBy(10.0), false);
+        map.addValidAfter(Integer.valueOf( 3), ref.shiftedBy( 2.0), false);
+        map.addValidAfter(Integer.valueOf( 9), ref.shiftedBy( 5.0), false);
+        map.addValidBefore(Integer.valueOf( 2), ref.shiftedBy( 3.0), false);
+        map.addValidBefore(Integer.valueOf( 5), ref.shiftedBy( 9.0), false);
+
+        TimeSpanMap.Span<Integer> first = map.getSpan(ref.shiftedBy(-99.0));
+        Assert.assertEquals(0, first.getData().intValue());
+        Assert.assertSame(AbsoluteDate.PAST_INFINITY, first.getStart());
+        Assert.assertNull(first.getStartTransition());
+        Assert.assertEquals(2.0, first.getEnd().durationFrom(ref), 1.0e-15);
+        Assert.assertNotNull(first.getEndTransition());
+
+        TimeSpanMap.Span<Integer> middle = map.getSpan(ref.shiftedBy(6.0));
+        Assert.assertEquals(5, middle.getData().intValue());
+        Assert.assertEquals(5.0, middle.getStart().durationFrom(ref), 1.0e-15);
+        Assert.assertNotNull(middle.getStartTransition());
+        Assert.assertEquals(9.0, middle.getEnd().durationFrom(ref), 1.0e-15);
+        Assert.assertNotNull(middle.getEndTransition());
+        Assert.assertSame(middle.getStartTransition().getAfter(), middle.getEndTransition().getBefore());
+        Assert.assertEquals(3, middle.getStartTransition().getBefore().intValue());
+        Assert.assertEquals(5, middle.getStartTransition().getAfter().intValue());
+        Assert.assertEquals(5, middle.getEndTransition().getBefore().intValue());
+        Assert.assertEquals(9, middle.getEndTransition().getAfter().intValue());
+
+        TimeSpanMap.Span<Integer> last = map.getSpan(ref.shiftedBy(+99.0));
+        Assert.assertEquals(10, last.getData().intValue());
+        Assert.assertEquals(10.0, last.getStart().durationFrom(ref), 1.0e-15);
+        Assert.assertNotNull(last.getStartTransition());
+        Assert.assertSame(AbsoluteDate.FUTURE_INFINITY, last.getEnd());
+        Assert.assertNull(last.getEndTransition());
+
+    }
+
     @Before
     public void setUp() {
         Utils.setDataRoot("regular-data");