Package it.unimi.dsi.util

Class Interval

java.lang.Object
java.util.AbstractCollection<Integer>
it.unimi.dsi.fastutil.ints.AbstractIntCollection
it.unimi.dsi.fastutil.ints.AbstractIntSet
it.unimi.dsi.fastutil.ints.AbstractIntSortedSet
it.unimi.dsi.util.Interval
All Implemented Interfaces:
IntBidirectionalIterable, IntCollection, IntIterable, IntSet, IntSortedSet, Serializable, Cloneable, Iterable<Integer>, Collection<Integer>, Set<Integer>, SortedSet<Integer>
public final class Interval
extends AbstractIntSortedSet
implements IntSortedSet, Serializable
An interval of integers. An interval is defined by two integers, called its left and right extremes, and contains all integers x such that left ≤ x ≤ right.

This class has no constructor: use the static factory methods valueOf(int, int) and valueOf(int), instead.

Instances of this class are immutable, and moreover implement the IntSortedSet interface. The equality method allows to check equality with both sorted and non-sorted sets of integers.

To reduce garbage collection, intervals made of one non-negative small points are precomputed and returned upon request.

See Also:
Serialized Form

  • Field Details

    • left

      public final int left
      The left extreme of the interval.

    • right

      public final int right
      The right extreme of the interval.

  • Constructor Details

    • Interval

      protected Interval​(int left, int right)
      Builds an interval with given extremes.

      You cannot generate an empty interval with this constructor. Use Intervals.EMPTY_INTERVAL instead.

      Parameters:
      left - the left extreme.
      right - the right extreme (which must be greater than or equal to the left extreme).

  • Method Details

    • valueOf

      public static Interval valueOf​(int left, int right)
      Returns an interval with given extremes.

      You cannot obtain an empty interval with this factory method. Use Intervals.EMPTY_INTERVAL instead.

      Parameters:
      left - the left extreme.
      right - the right extreme (which must be greater than or equal to the left extreme).
      Returns:
      an interval with the given extremes.

    • valueOf

      public static Interval valueOf​(int point)
      Returns a one-point interval.

      You cannot obtain an empty interval with this factory method. Use Intervals.EMPTY_INTERVAL instead.

      Parameters:
      point - a point.
      Returns:
      a one-point interval

    • length

      public int length()
      Returns the interval length, that is, the number of integers contained in the interval.
      Returns:
      the interval length.

    • size

      public int size()
      An alias for length().
      Specified by:
      size in interface Collection<Integer>
      Specified by:
      size in interface Set<Integer>
      Specified by:
      size in class AbstractCollection<Integer>
      Returns:
      the interval length.

    • iterator

      public IntBidirectionalIterator iterator()
      Returns an iterator over the integers in this interval.
      Specified by:
      iterator in interface Collection<Integer>
      Specified by:
      iterator in interface IntBidirectionalIterable
      Specified by:
      iterator in interface IntCollection
      Specified by:
      iterator in interface IntIterable
      Specified by:
      iterator in interface IntSet
      Specified by:
      iterator in interface IntSortedSet
      Specified by:
      iterator in interface Iterable<Integer>
      Specified by:
      iterator in interface Set<Integer>
      Specified by:
      iterator in class AbstractIntSortedSet
      Returns:
      an integer iterator over the elements in this interval.

    • iterator

      public IntBidirectionalIterator iterator​(int from)
      Returns an iterator over the integers in this interval larger than or equal to a given integer.
      Specified by:
      iterator in interface IntSortedSet
      Parameters:
      from - the starting integer.
      Returns:
      an integer iterator over the elements in this interval.

    • contains

      public boolean contains​(int x)
      Checks whether this interval contains the specified integer.
      Specified by:
      contains in interface IntCollection
      Overrides:
      contains in class AbstractIntCollection
      Parameters:
      x - an integer.
      Returns:
      whether this interval contains x, that is, whether left ≤ x ≤ right.

    • contains

      public boolean contains​(Interval interval)
      Checks whether this interval contains the specified interval.
      Parameters:
      interval - an interval.
      Returns:
      whether this interval contains (as a set) interval.

    • contains

      public boolean contains​(int x, int radius)
      Checks whether this interval would contain the specified integer if enlarged in both directions by the specified radius.
      Parameters:
      x - an integer.
      radius - the radius.
      Returns:
      whether this interval enlarged by radius would contain x, e.g., whether left−radius ≤ x ≤ right+radius.

    • contains

      public boolean contains​(int x, int leftRadius, int rightRadius)
      Checks whether this interval would contain the specified integer if enlarged in each direction with the respective radius. directions by the specified radius.
      Parameters:
      x - an integer.
      leftRadius - the left radius.
      rightRadius - the right radius.
      Returns:
      whether this interval enlarged to the left by leftRadius and to the right by rightRadius would contain x, e.g., whether left−leftRadius ≤ x ≤ right+rightRadius.

    • compareTo

      public int compareTo​(int x)
      Compares this interval to an integer.
      Parameters:
      x - an integer.
      Returns:
      a negative integer, zero, or a positive integer as x is positioned at the left, belongs, or is positioned to the right of this interval, e.g., as x < left, left ≤ x ≤ right or right < x.

    • compareTo

      public int compareTo​(int x, int radius)
      Compares this interval to an integer with a specified radius.
      Parameters:
      x - an integer.
      radius - the radius.
      Returns:
      a negative integer, zero, or a positive integer as x is positioned at the left, belongs, or is positioned to the right of this interval enlarged by radius, that is, as x < left−radius, left−radius ≤ x ≤ right+radius or right+radius < x.

    • compareTo

      public int compareTo​(int x, int leftRadius, int rightRadius)
      Compares this interval to an integer with specified left and right radii.
      Parameters:
      x - an integer.
      leftRadius - the left radius.
      rightRadius - the right radius.
      Returns:
      a negative integer, zero, or a positive integer as x is positioned at the left, belongs, or is positioned to the right of this interval enlarged by leftRadius on the left and rightRadius in the right, that is, as x < left−leftRadius, left−leftRadius ≤ x ≤ right+rightRadius or right+rightRadius < x.

    • comparator

      public IntComparator comparator()
      Specified by:
      comparator in interface IntSortedSet
      Specified by:
      comparator in interface SortedSet<Integer>

    • headSet

      public IntSortedSet headSet​(int to)
      Specified by:
      headSet in interface IntSortedSet

    • tailSet

      public IntSortedSet tailSet​(int from)
      Specified by:
      tailSet in interface IntSortedSet

    • subSet

      public IntSortedSet subSet​(int from, int to)
      Specified by:
      subSet in interface IntSortedSet

    • firstInt

      public int firstInt()
      Specified by:
      firstInt in interface IntSortedSet

    • lastInt

      public int lastInt()
      Specified by:
      lastInt in interface IntSortedSet

    • toString

      public String toString()
      Overrides:
      toString in class AbstractIntCollection

    • hashCode

      public int hashCode()
      Specified by:
      hashCode in interface Collection<Integer>
      Specified by:
      hashCode in interface Set<Integer>
      Overrides:
      hashCode in class AbstractIntSet

    • equals

      public boolean equals​(Object o)
      Checks whether this interval is equal to another set of integers.
      Specified by:
      equals in interface Collection<Integer>
      Specified by:
      equals in interface Set<Integer>
      Overrides:
      equals in class AbstractIntSet
      Parameters:
      o - an object.
      Returns:
      true if o is an ordered set of integer containing the same element of this interval in the same order, or if o is a set of integers containing the same elements of this interval.