Package org.apache.lucene.codecs.bloom
Class MurmurHash2
java.lang.Object
org.apache.lucene.codecs.bloom.HashFunction
org.apache.lucene.codecs.bloom.MurmurHash2
This is a very fast, non-cryptographic hash suitable for general hash-based lookup. See
http://murmurhash.googlepages.com/ for more details.
The C version of MurmurHash 2.0 found at that site was ported to Java by Andrzej Bialecki (ab at getopt org).
The code from getopt.org was adapted by Mark Harwood in the form here as one of a pluggable choice of hashing functions as the core function had to be adapted to work with BytesRefs with offsets and lengths rather than raw byte arrays.
- WARNING: This API is experimental and might change in incompatible ways in the next release.
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Field Summary
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Method Summary
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Field Details
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INSTANCE
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Method Details
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hash
public static int hash(byte[] data, int seed, int offset, int len) -
hash32
public static final int hash32(byte[] data, int offset, int len) Generates 32 bit hash from byte array with default seed value.- Parameters:
data
- byte array to hashoffset
- the start position in the array to hashlen
- length of the array elements to hash- Returns:
- 32 bit hash of the given array
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hash
Description copied from class:HashFunction
Hashes the contents of the referenced bytes- Specified by:
hash
in classHashFunction
- Parameters:
br
- the data to be hashed- Returns:
- the hash of the bytes referenced by bytes.offset and length bytes.length
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toString
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