Class DiscreteDomain<C extends Comparable>

java.lang.Object
com.google.common.collect.DiscreteDomain<C>
@GwtCompatible public abstract class DiscreteDomain<C extends Comparable> extends Object
A descriptor for a discrete Comparable domain such as all Integer instances. A discrete domain is one that supports the three basic operations: next(C), previous(C) and distance(C, C), according to their specifications. The methods minValue() and maxValue() should also be overridden for bounded types.

A discrete domain always represents the entire set of values of its type; it cannot represent partial domains such as "prime integers" or "strings of length 5."

See the Guava User Guide section on DiscreteDomain.

Since:
10.0
Author:
Kevin Bourrillion

  • Constructor Details

    • DiscreteDomain

      protected DiscreteDomain()
      Constructor for use by subclasses.

  • Method Details

    • integers

      public static DiscreteDomain<Integer> integers()
      Returns the discrete domain for values of type Integer.

      This method always returns the same object. That object is serializable; deserializing it results in the same object too.

      Since:
      14.0 (since 10.0 as DiscreteDomains.integers())

    • longs

      public static DiscreteDomain<Long> longs()
      Returns the discrete domain for values of type Long.

      This method always returns the same object. That object is serializable; deserializing it results in the same object too.

      Since:
      14.0 (since 10.0 as DiscreteDomains.longs())

    • bigIntegers

      public static DiscreteDomain<BigInteger> bigIntegers()
      Returns the discrete domain for values of type BigInteger.

      This method always returns the same object. That object is serializable; deserializing it results in the same object too.

      Since:
      15.0

    • next

      public abstract @Nullable C next(C value)
      Returns the unique least value of type C that is greater than value, or null if none exists. Inverse operation to previous(C).
      Parameters:
      value - any value of type C
      Returns:
      the least value greater than value, or null if value is maxValue()

    • previous

      public abstract @Nullable C previous(C value)
      Returns the unique greatest value of type C that is less than value, or null if none exists. Inverse operation to next(C).
      Parameters:
      value - any value of type C
      Returns:
      the greatest value less than value, or null if value is minValue()

    • distance

      public abstract long distance(C start, C end)
      Returns a signed value indicating how many nested invocations of next(C) (if positive) or previous(C) (if negative) are needed to reach end starting from start. For example, if end = next(next(next(start))), then distance(start, end) == 3 and distance(end, start) == -3. As well, distance(a, a) is always zero.

      Note that this function is necessarily well-defined for any discrete type.

      Returns:
      the distance as described above, or Long.MIN_VALUE or Long.MAX_VALUE if the distance is too small or too large, respectively.

    • minValue

      @CanIgnoreReturnValue public C minValue()
      Returns the minimum value of type C, if it has one. The minimum value is the unique value for which Comparable.compareTo(Object) never returns a positive value for any input of type C.

      The default implementation throws NoSuchElementException.

      Returns:
      the minimum value of type C; never null
      Throws:
      NoSuchElementException - if the type has no (practical) minimum value; for example, BigInteger

    • maxValue

      @CanIgnoreReturnValue public C maxValue()
      Returns the maximum value of type C, if it has one. The maximum value is the unique value for which Comparable.compareTo(Object) never returns a negative value for any input of type C.

      The default implementation throws NoSuchElementException.

      Returns:
      the maximum value of type C; never null
      Throws:
      NoSuchElementException - if the type has no (practical) maximum value; for example, BigInteger