Package com.google.common.hash

Class BloomFilter<T>

java.lang.Object
com.google.common.hash.BloomFilter<T>
Type Parameters:
T - the type of instances that the BloomFilter accepts
All Implemented Interfaces:
Predicate<T>, Serializable
@Beta @Deprecated(since="2022-12-01") public final class BloomFilter<T> extends Object implements Predicate<T>, Serializable
Deprecated.
The Google Guava Core Libraries are deprecated and will not be part of the AEM SDK after April 2023
A Bloom filter for instances of T. A Bloom filter offers an approximate containment test with one-sided error: if it claims that an element is contained in it, this might be in error, but if it claims that an element is not contained in it, then this is definitely true.

If you are unfamiliar with Bloom filters, this nice tutorial may help you understand how they work.

The false positive probability (FPP) of a bloom filter is defined as the probability that mightContain(Object) will erroneously return true for an object that has not actually been put in the BloomFilter.

Since:
11.0
See Also:

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    apply(T input)
    Deprecated.
    Equivalent to mightContain(T); provided only to satisfy the Predicate interface.
    BloomFilter<T>
    copy()
    Deprecated.
    Creates a new BloomFilter that's a copy of this instance.
    static <T> BloomFilter<T>
    create(Funnel<T> funnel, int expectedInsertions)
    Deprecated.
    Creates a BloomFilter with the expected number of insertions and a default expected false positive probability of 3%.
    static <T> BloomFilter<T>
    create(Funnel<T> funnel, int expectedInsertions, double fpp)
    Deprecated.
    Creates a BloomFilter with the expected number of insertions and expected false positive probability.
    boolean
    equals(Object object)
    Deprecated.
    Indicates whether another object is equal to this predicate.
    double
    expectedFpp()
    Deprecated.
    Returns the probability that mightContain(Object) will erroneously return true for an object that has not actually been put in the BloomFilter.
    int
    hashCode()
    Deprecated.
     
    boolean
    isCompatible(BloomFilter<T> that)
    Deprecated.
    Determines whether a given bloom filter is compatible with this bloom filter.
    boolean
    mightContain(T object)
    Deprecated.
    Returns true if the element might have been put in this Bloom filter, false if this is definitely not the case.
    boolean
    put(T object)
    Deprecated.
    Puts an element into this BloomFilter.
    void
    putAll(BloomFilter<T> that)
    Deprecated.
    Combines this bloom filter with another bloom filter by performing a bitwise OR of the underlying data.

    Methods inherited from class java.lang.Object

    getClass, notify, notifyAll, toString, wait, wait, wait

  • Method Details

    • copy

      public BloomFilter<T> copy()
      Deprecated.
      Creates a new BloomFilter that's a copy of this instance. The new instance is equal to this instance but shares no mutable state.
      Since:
      12.0

    • mightContain

      public boolean mightContain(T object)
      Deprecated.
      Returns true if the element might have been put in this Bloom filter, false if this is definitely not the case.

    • apply

      public boolean apply(T input)
      Deprecated.
      Equivalent to mightContain(T); provided only to satisfy the Predicate interface. When using a reference of type BloomFilter, always invoke mightContain(T) directly instead.
      Specified by:
      apply in interface Predicate<T>

    • put

      public boolean put(T object)
      Deprecated.
      Puts an element into this BloomFilter. Ensures that subsequent invocations of mightContain(Object) with the same element will always return true.
      Returns:
      true if the bloom filter's bits changed as a result of this operation. If the bits changed, this is definitely the first time object has been added to the filter. If the bits haven't changed, this might be the first time object has been added to the filter. Note that put(t) always returns the opposite result to what mightContain(t) would have returned at the time it is called."
      Since:
      12.0 (present in 11.0 with void return type})

    • expectedFpp

      public double expectedFpp()
      Deprecated.
      Returns the probability that mightContain(Object) will erroneously return true for an object that has not actually been put in the BloomFilter.

      Ideally, this number should be close to the fpp parameter passed in create(Funnel, int, double), or smaller. If it is significantly higher, it is usually the case that too many elements (more than expected) have been put in the BloomFilter, degenerating it.

      Since:
      14.0 (since 11.0 as expectedFalsePositiveProbability())

    • isCompatible

      public boolean isCompatible(BloomFilter<T> that)
      Deprecated.
      Determines whether a given bloom filter is compatible with this bloom filter. For two bloom filters to be compatible, they must:
      • not be the same instance
      • have the same number of hash functions
      • have the same bit size
      • have the same strategy
      • have equal funnels
        Parameters:
        that - The bloom filter to check for compatibility.
        Since:
        15.0

      • putAll

        public void putAll(BloomFilter<T> that)
        Deprecated.
        Combines this bloom filter with another bloom filter by performing a bitwise OR of the underlying data. The mutations happen to this instance. Callers must ensure the bloom filters are appropriately sized to avoid saturating them.
        Parameters:
        that - The bloom filter to combine this bloom filter with. It is not mutated.
        Throws:
        IllegalArgumentException - if isCompatible(that) == false
        Since:
        15.0

      • equals

        public boolean equals(@Nullable Object object)
        Deprecated.
        Description copied from interface: Predicate
        Indicates whether another object is equal to this predicate.

        Most implementations will have no reason to override the behavior of Object.equals(java.lang.Object). However, an implementation may also choose to return true whenever object is a Predicate that it considers interchangeable with this one. "Interchangeable" typically means that this.apply(t) == that.apply(t) for all t of type T). Note that a false result from this method does not imply that the predicates are known not to be interchangeable.

        Specified by:
        equals in interface Predicate<T>
        Overrides:
        equals in class Object

      • hashCode

        public int hashCode()
        Deprecated.
        Overrides:
        hashCode in class Object

      • create

        public static <T> BloomFilter<T> create(Funnel<T> funnel, int expectedInsertions, double fpp)
        Deprecated.
        Creates a BloomFilter with the expected number of insertions and expected false positive probability.

        Note that overflowing a BloomFilter with significantly more elements than specified, will result in its saturation, and a sharp deterioration of its false positive probability.

        The constructed BloomFilter<T> will be serializable if the provided Funnel<T> is.

        It is recommended that the funnel be implemented as a Java enum. This has the benefit of ensuring proper serialization and deserialization, which is important since equals(java.lang.Object) also relies on object identity of funnels.

        Parameters:
        funnel - the funnel of T's that the constructed BloomFilter<T> will use
        expectedInsertions - the number of expected insertions to the constructed BloomFilter<T>; must be positive
        fpp - the desired false positive probability (must be positive and less than 1.0)
        Returns:
        a BloomFilter

      • create

        public static <T> BloomFilter<T> create(Funnel<T> funnel, int expectedInsertions)
        Deprecated.
        Creates a BloomFilter with the expected number of insertions and a default expected false positive probability of 3%.

        Note that overflowing a BloomFilter with significantly more elements than specified, will result in its saturation, and a sharp deterioration of its false positive probability.

        The constructed BloomFilter<T> will be serializable if the provided Funnel<T> is.

        Parameters:
        funnel - the funnel of T's that the constructed BloomFilter<T> will use
        expectedInsertions - the number of expected insertions to the constructed BloomFilter<T>; must be positive
        Returns:
        a BloomFilter