assertNotNull(e);
        }
    }

    // Test various numeric values for time adjust
    public void xtest_getTimeAdjustTimeMillisAsLong_variousValues() {
        // Test negative value
        FessEnv.SimpleImpl negativeEnv = new FessEnv.SimpleImpl() {
            protected Properties prepareProperties() {
                Properties props = new Properties();

 * This is either a mapping decision or the length of the mapped output, according to this table:
 *
 * ```
 *  0..63 : Length of the UTF-16 sequence that this range maps to. The offset is b2b3.
 * 64..79 : Offset by a fixed negative offset. The bottom 4 bits of b1 are the top 4 bits of the offset.
 * 80..95 : Offset by a fixed positive offset. The bottom 4 bits of b1 are the top 4 bits of the offset.
 *    119 : Ignored.
 *    120 : Valid.

      }
    }
    return s;
  }

  /** Escapes the given Unicode code point in UTF-8. */
  @Override
  protected char @Nullable [] escape(int cp) {
    // We should never get negative values here but if we do it will throw an
    // IndexOutOfBoundsException, so at least it will get spotted.
    if (cp < safeOctets.length && safeOctets[cp]) {
      return null;
    } else if (cp == ' ' && plusForSpace) {

 *
 * @author Colin Decker
 */
final class SubscriberRegistry {

  /**
   * All registered subscribers, indexed by event type.
   *
   * <p>The {@link CopyOnWriteArraySet} values make it easy and relatively lightweight to get an
   * immutable snapshot of all current subscribers to an event without any locking.
   */
  private final ConcurrentMap<Class<?>, CopyOnWriteArraySet<Subscriber>> subscribers =

        )
        if (dateCharacter == !invert) return i
      }
      return limit
    }

    /**
     * Returns the positive value if [s] is positive, or [Long.MIN_VALUE] if it is either 0 or
     * negative. If the value is positive but out of range, this returns [Long.MAX_VALUE].
     *
     * @throws NumberFormatException if [s] is not an integer of any precision.
     */
    private fun parseMaxAge(s: String): Long {

  }

  @CanIgnoreReturnValue
  static int checkNonNegative(int value) {
    checkArgument(value >= 0, "Not true that %s is non-negative.", value);
    return value;
  }

  @CanIgnoreReturnValue
  static long checkNonNegative(long value) {
    checkArgument(value >= 0, "Not true that %s is non-negative.", value);
    return value;
  }

  @CanIgnoreReturnValue
  static int checkPositive(int value) {

  }

  @CanIgnoreReturnValue
  static int checkNonNegative(int value) {
    checkArgument(value >= 0, "Not true that %s is non-negative.", value);
    return value;
  }

  @CanIgnoreReturnValue
  static long checkNonNegative(long value) {
    checkArgument(value >= 0, "Not true that %s is non-negative.", value);
    return value;
  }

  @CanIgnoreReturnValue
  static int checkPositive(int value) {

        // Check watch tree flag
        assertEquals(0x01, dst[16]);

        // Check reserved byte is zero
        assertEquals(0x00, dst[17]);
    }

    @Test
    @DisplayName("Test with negative FID value (should handle as unsigned)")
    void testNegativeFidValue() {
        int fid = -1; // Will be treated as 0xFFFF in unsigned 16-bit

    assertThrows(
        NumberFormatException.class,
        () -> UnsignedLongs.parseUnsignedLong("0", Character.MAX_RADIX + 1));

    // The radix is used as an array index, so try a negative value.
    assertThrows(NumberFormatException.class, () -> UnsignedLongs.parseUnsignedLong("0", -1));
  }

  public void testToString() {
    String[] tests = {
      "0",
      "ffffffffffffffff",

        assertEquals(0, response.readParametersWireFormat(emptyBuffer, 0, 0));
        assertEquals(0, response.readDataWireFormat(emptyBuffer, 0, 0));
    }

    @Test
    @DisplayName("Methods should handle negative indices")
    void testMethodsWithNegativeIndices() {
        // Arrange
        byte[] buffer = new byte[100];
        int negativeIndex = -1;

        // Act & Assert