Package org.apache.cassandra.dht

Class Range<T extends RingPosition<T>>

  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Comparable<Range<T>>
    Direct Known Subclasses:
    MerkleTree.TreeRange
    public class Range<T extends RingPosition<T>>
extends AbstractBounds<T>
implements java.lang.Comparable<Range<T>>, java.io.Serializable
    A representation of the range that a node is responsible for on the DHT ring. A Range is responsible for the tokens between (left, right]. Used by the partitioner and by map/reduce by-token range scans. Note: this class has a natural ordering that is inconsistent with equals
    See Also:
    Serialized Form

    • Constructor Detail

      • Range

        public Range​(T left,
             T right)

    • Method Detail

      • contains

        public static <T extends RingPosition<T>> boolean contains​(T left,
                                                           T right,
                                                           T point)

      • contains

        public boolean contains​(Range<T> that)

      • contains

        public boolean contains​(T point)
        Helps determine if a given point on the DHT ring is contained in the range in question.
        Specified by:
        contains in class AbstractBounds<T extends RingPosition<T>>
        Parameters:
        point - point in question
        Returns:
        true if the point contains within the range else false.

      • intersects

        public boolean intersects​(Range<T> that)
        Parameters:
        that - range to check for intersection
        Returns:
        true if the given range intersects with this range.

      • intersects

        public boolean intersects​(Bounds<T> that)
        Parameters:
        that - range to check for intersection
        Returns:
        true if the given range intersects with this range.

      • intersects

        public static boolean intersects​(java.lang.Iterable<Range<Token>> l,
                                 java.lang.Iterable<Range<Token>> r)

      • rangeSet

        @SafeVarargs
public static <T extends RingPosition<T>> java.util.Set<Range<T>> rangeSet​(Range<T>... ranges)

      • intersectionWith

        public java.util.Set<Range<T>> intersectionWith​(Range<T> that)
        Parameters:
        that -
        Returns:
        the intersection of the two Ranges. this can be two disjoint Ranges if one is wrapping and one is not. say you have nodes G and M, with query range (D,T]; the intersection is (M-T] and (D-G]. If there is no intersection, an empty list is returned.

      • intersectionNonWrapping

        public Range<T> intersectionNonWrapping​(Range<T> that)
        Returns the intersection of this range with the provided one, assuming neither are wrapping.
        Parameters:
        that - the other range to return the intersection with. It must not be wrapping.
        Returns:
        the intersection of this and that, or null if both ranges don't intersect.

      • split

        public Pair<AbstractBounds<T>,​AbstractBounds<T>> split​(T position)
        Description copied from class: AbstractBounds
        Given token T and AbstractBounds ?L,R?, returns Pair(?L,T], (T,R?), where ? means that the same type of AbstractBounds is returned as the original. Put another way, returns a Pair of everything this AbstractBounds contains up to and including the split position, and everything it contains after (not including the split position). The original AbstractBounds must either contain the position T, or T should be equals to the left bound L. If the split would only yield the same AbstractBound, null is returned instead.
        Specified by:
        split in class AbstractBounds<T extends RingPosition<T>>

      • isWrapAround

        public static <T extends RingPosition<T>> boolean isWrapAround​(T left,
                                                               T right)
        Tells if the given range is a wrap around.

      • isTrulyWrapAround

        public boolean isTrulyWrapAround()
        Checks if the range truly wraps around. This exists only because isWrapAround() is a tad dumb and return true if right is the minimum token, no matter what left is, but for most intent and purposes, such range doesn't truly warp around (unwrap produces the identity in this case).

        Also note that it could be that the remaining uses of isWrapAround() could be replaced by this method, but that is to be checked carefully at some other time (Sylvain).

        The one thing this method guarantees is that if it's true, then unwrap() will return a list with exactly 2 ranges, never one.

      • isTrulyWrapAround

        public static <T extends RingPosition<T>> boolean isTrulyWrapAround​(T left,
                                                                    T right)

      • compareTo

        public int compareTo​(Range<T> rhs)
        Note: this class has a natural ordering that is inconsistent with equals
        Specified by:
        compareTo in interface java.lang.Comparable<T extends RingPosition<T>>

      • subtract

        public java.util.Set<Range<T>> subtract​(Range<T> rhs)

      • subtractAll

        public java.util.Set<Range<T>> subtractAll​(java.util.Collection<Range<T>> ranges)

      • subtract

        public static <T extends RingPosition<T>> java.util.Set<Range<T>> subtract​(java.util.Collection<Range<T>> ranges,
                                                                           java.util.Collection<Range<T>> subtract)

      • differenceToFetch

        public java.util.Set<Range<T>> differenceToFetch​(Range<T> rhs)
        Calculate set of the difference ranges of given two ranges (as current (A, B] and rhs is (C, D]) which node will need to fetch when moving to a given new token
        Parameters:
        rhs - range to calculate difference
        Returns:
        set of difference ranges

      • isInRanges

        public static <T extends RingPosition<T>> boolean isInRanges​(T token,
                                                             java.lang.Iterable<Range<T>> ranges)

      • equals

        public boolean equals​(java.lang.Object o)
        Overrides:
        equals in class java.lang.Object

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object

      • asList

        public java.util.List<java.lang.String> asList()

      • isWrapAround

        public boolean isWrapAround()

      • normalize

        public static <T extends RingPosition<T>> java.util.List<Range<T>> normalize​(java.util.Collection<Range<T>> ranges)
        Returns:
        A copy of the given list of with all ranges unwrapped, sorted by left bound and with overlapping bounds merged.

      • deoverlap

        public static <T extends RingPosition<T>> java.util.List<Range<T>> deoverlap​(java.util.List<Range<T>> ranges)
        Given a list of unwrapped ranges sorted by left position, return an equivalent list of ranges but with no overlapping ranges.

      • sort

        public static <T extends RingPosition<T>> java.util.List<Range<T>> sort​(java.util.Collection<Range<T>> ranges)

      • makeRowRange

        public static Range<PartitionPosition> makeRowRange​(Token left,
                                                    Token right)
        Compute a range of keys corresponding to a given range of token.

      • assertNormalized

        public static <T extends RingPosition<T>> void assertNormalized​(java.util.List<Range<T>> ranges)