## org.apache.cassandra.utils
Class BloomFilter

    java.lang.Object
      org.apache.cassandra.utils.Filter
          org.apache.cassandra.utils.BloomFilter

    public class BloomFilter

extends Filter

Method Summary
`void` `add(byte[] key)`
`void` `add(java.lang.String key)`
`static BloomFilter` `alwaysMatchingBloomFilter()`
`void` `clear()`
`static BloomFilter` `getFilter(long numElements, double maxFalsePosProbability)`
`static BloomFilter` `getFilter(long numElements, int targetBucketsPerElem)`
`boolean` `isPresent(byte[] key)`
`boolean` `isPresent(java.lang.String key)`
`static ICompactSerializer<BloomFilter>` `serializer()`
`java.lang.String` `toString()`

Methods inherited from class org.apache.cassandra.utils.Filter
`getHashBuckets, getHashBuckets`

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

Method Detail

### serializer

    public static ICompactSerializer<BloomFilter> serializer()

### getFilter

    public static BloomFilter getFilter(long numElements,
                                        int targetBucketsPerElem)

  Returns:
    A BloomFilter with the lowest practical false positive probability for the given number of elements.

### getFilter

    public static BloomFilter getFilter(long numElements,
                                        double maxFalsePosProbability)

  Returns:
    The smallest BloomFilter that can provide the given false positive probability rate for the given number of elements. Asserts that the given probability can be satisfied using this filter.

### clear

    public void clear()

### isPresent

    public boolean isPresent(java.lang.String key)

  Specified by:
    `isPresent` in class `Filter`

### isPresent

    public boolean isPresent(byte[] key)

### add

    public void add(java.lang.String key)

  Specified by:
    `add` in class `Filter`

### add

    public void add(byte[] key)

### toString

    public java.lang.String toString()

  Overrides:
    `toString` in class `java.lang.Object`

### alwaysMatchingBloomFilter

    public static BloomFilter alwaysMatchingBloomFilter()

  Returns:
    a BloomFilter that always returns a positive match, for testing

Copyright © 2010 The Apache Software Foundation