chore: LongRange Does Not Support Empty Range

* Removed the special case for `-1 -> -1` LongRange
  * We used to have this to denote "empty" range
  * We've since moved on from this, because this is extra complexity
    with no added benefit
* Fixed unit tests that asserted the possibility of `-1 -> -1` LongRange

NOTE: This change also comes with the need to validate that we do not
disrupt or break current logic, which _could_ be using the empty range
notion! LongRange has almost 400 usages at the time of this commit.
Thorough walkthrough is needed to validate that nothing is broken.

Signed-off-by: Atanas Atanasov <a.v.atanasov98@gmail.com>

Author: ata-nas

block-node/spi-plugins/src/main/java/org/hiero/block/node/spi/historicalblocks/LongRange.java

@@ -7,59 +7,41 @@
 
 /**
  * Contiguous range of long values, inclusive of start and end.
- * Valid ranges must have start and end values between 0 and Long.MAX_VALUE-1 inclusive,
- * with start less than or equal to end. This ensures that the size() method can correctly
- * represent any valid range with a long value without risk of overflow.
+ * Valid ranges must have start and end values between 0 and Long.MAX_VALUE-1
+ * inclusive, with start less than or equal to end. This ensures that the size()
+ * method can correctly represent any valid range with a long value without risk
+ * of overflow.
  */
 public record LongRange(long start, long end) implements Comparable<LongRange> {
-
     /** Comparator for comparing LongRange objects by their start and end values. */
     public static final Comparator<LongRange> COMPARATOR =
             Comparator.comparingLong(LongRange::start).thenComparingLong(LongRange::end);
 
     /**
      * Creates a new LongRange with the specified start and end values.
      *
-     * @param start the start value of the range (inclusive), must be between 0 and Long.MAX_VALUE-1
-     * @param end the end value of the range (inclusive), must be between 0 and Long.MAX_VALUE-1
-     * @throws IllegalArgumentException if start or end is negative or greater than Long.MAX_VALUE-1,
-     *                                  or if start is greater than end
+     * @param start the start value of the range (inclusive), must be between 0
+     * and Long.MAX_VALUE-1
+     * @param end the end value of the range (inclusive), must be between 0 and
+     * Long.MAX_VALUE-1
+     * @throws IllegalArgumentException if start or end is negative or greater
+     * than Long.MAX_VALUE-1, or if start is greater than end
      */
     public LongRange {
-        // Special case: allow both start and end to be -1 for clean state initialization
-        if (!(start == -1 && end == -1)) {
-            if (start < 0) {
-                throw new IllegalArgumentException("Range start must be non-negative: " + start);
-            }
-            if (end < 0) {
-                throw new IllegalArgumentException("Range end must be non-negative: " + end);
-            }
-            if (start > end) {
-                throw new IllegalArgumentException(
-                        "Range start must be less than or equal to end: " + start + " > " + end);
-            }
-            if (end > Long.MAX_VALUE - 1) {
-                throw new IllegalArgumentException("Range end must be less than or equal to Long.MAX_VALUE-1: " + end);
-            }
+        if (start < 0) {
+            throw new IllegalArgumentException("LongRange start: %d must not be negative".formatted(start));
+        }
+        if (end < 0) {
+            throw new IllegalArgumentException("LongRange end: %d must not be negative".formatted(end));
+        }
+        if (end > Long.MAX_VALUE - 1) {
+            throw new IllegalArgumentException(
+                    "LongRange end: %d must not be greater than Long.MAX_VALUE-1".formatted(end));
+        }
+        if (start > end) {
+            throw new IllegalArgumentException(
+                    "LongRange start: %d must not be greater than end: %d".formatted(start, end));
         }
-    }
-
-    /**
-     * Gets the start value of the range, inclusive.
-     *
-     * @return the start value of the range
-     */
-    public long start() {
-        return start;
-    }
-
-    /**
-     * Gets the end value of the range, inclusive.
-     *
-     * @return the end value of the range
-     */
-    public long end() {
-        return end;
     }
 
     /**
@@ -68,25 +50,34 @@ public long end() {
      * @param value the value to check
      * @return true if the range contains the value, false otherwise
      */
-    public boolean contains(long value) {
+    public boolean contains(final long value) {
         return value >= start && value <= end;
     }
 
+    private static final String INVALID_VALUES_TO_COMPARE_MSG =
+            "Provided start: %d value to compare must be equal to or lower than provided end: %d value to compare";
+
     /**
-     * Checks if the range contains another range specified by start and end values.
+     * Checks if the range contains another range specified by start and end
+     * values.
      *
      * @param start the start value of the range to check
      * @param end the end value of the range to check
      * @return true if the range contains the specified range, false otherwise
      */
-    public boolean contains(long start, long end) {
-        return start >= this.start && end <= this.end;
+    public boolean contains(final long start, final long end) {
+        if (start > end) {
+            throw new IllegalArgumentException(INVALID_VALUES_TO_COMPARE_MSG.formatted(start, end));
+        } else {
+            return start >= this.start && end <= this.end;
+        }
     }
 
     /**
      * Gets the size of the range.
      *
-     * @return the size of the range (number of elements), computed as end - start + 1
+     * @return the size of the range (number of elements),
+     * computed as end - start + 1
      */
     public long size() {
         return end - start + 1;
@@ -98,7 +89,7 @@ public long size() {
      * @param other the other range to check
      * @return true if the ranges overlap, false otherwise
      */
-    public boolean overlaps(LongRange other) {
+    public boolean overlaps(final LongRange other) {
         return !(end < other.start() || start > other.end());
     }
 
@@ -118,7 +109,7 @@ public boolean isAdjacent(LongRange other) {
      * @param other the other range to merge with
      * @return a new ImmutableLongRange representing the merged range
      */
-    public LongRange merge(LongRange other) {
+    public LongRange merge(final LongRange other) {
         return new LongRange(Math.min(start, other.start()), Math.max(end, other.end()));
     }
 
@@ -135,11 +126,11 @@ public LongStream stream() {
      * Compares this range to another range.
      *
      * @param o the other range to compare to
-     * @return a negative integer, zero, or a positive integer as this range is less than, equal to, or greater than
-     * the specified range
+     * @return a negative integer, zero, or a positive integer as this range is
+     * less than, equal to, or greater than the specified range
      */
     @Override
-    public int compareTo(@NonNull LongRange o) {
+    public int compareTo(@NonNull final LongRange o) {
         return COMPARATOR.compare(this, o);
     }
 
@@ -148,6 +139,7 @@ public int compareTo(@NonNull LongRange o) {
      *
      * @return a string representation of the range in the format "start->end"
      */
+    @NonNull
     @Override
     public String toString() {
         return start + "->" + end;

block-node/spi-plugins/src/test/java/org/hiero/block/node/spi/historicalblocks/LongRangeTest.java

@@ -37,12 +37,8 @@ void testConstructor() {
         assertEquals(10, range3.start());
         assertEquals(10, range3.end());
 
-        // Test special case for clean state initialization
-        final LongRange cleanStateRange = new LongRange(-1, -1);
-        assertEquals(-1, cleanStateRange.start());
-        assertEquals(-1, cleanStateRange.end());
-
         // Test validation failures
+        assertThrows(IllegalArgumentException.class, () -> new LongRange(-1, -1));
         assertThrows(IllegalArgumentException.class, () -> new LongRange(-1, 5));
         assertThrows(IllegalArgumentException.class, () -> new LongRange(5, -1));
         assertThrows(IllegalArgumentException.class, () -> new LongRange(6, 5));