com.google.common.hash

Class Murmur3_32HashFunction

java.lang.Object

com.google.common.hash.AbstractStreamingHashFunction

com.google.common.hash.Murmur3_32HashFunction

All Implemented Interfaces:

HashFunction, java.io.Serializable

final class Murmur3_32HashFunction
extends AbstractStreamingHashFunction
implements java.io.Serializable

See MurmurHash3_x86_32 in the C++ implementation.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	Murmur3_32HashFunction.Murmur3_32Hasher

Nested classes/interfaces inherited from class com.google.common.hash.AbstractStreamingHashFunction

AbstractStreamingHashFunction.AbstractStreamingHasher

Field Summary

Fields

Modifier and Type	Field and Description
private static int	C1
private static int	C2
private int	seed
private static long	serialVersionUID

Constructor Summary

Constructors

Constructor and Description
Murmur3_32HashFunction(int seed)

Method Summary

Modifier and Type	Method and Description
int	bits() Returns the number of bits (a multiple of 32) that each hash code produced by this hash function has.
boolean	equals(java.lang.Object object)
private static HashCode	fmix(int h1, int length)
int	hashCode()
HashCode	hashInt(int input) Shortcut for newHasher().putInt(input).hash(); returns the hash code for the given int value, interpreted in little-endian byte order.
HashCode	hashLong(long input) Shortcut for newHasher().putLong(input).hash(); returns the hash code for the given long value, interpreted in little-endian byte order.
HashCode	hashUnencodedChars(java.lang.CharSequence input) Shortcut for newHasher().putUnencodedChars(input).hash().
private static int	mixH1(int h1, int k1)
private static int	mixK1(int k1)
Hasher	newHasher() Begins a new hash code computation by returning an initialized, stateful Hasher instance that is ready to receive data.
java.lang.String	toString()

Methods inherited from class com.google.common.hash.AbstractStreamingHashFunction

hashBytes, hashBytes, hashObject, hashString, newHasher

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

C1

private static final int C1

See Also:

Constant Field Values

C2

private static final int C2

See Also:

Constant Field Values

seed

private final int seed

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

Constructor Detail

Murmur3_32HashFunction

Murmur3_32HashFunction(int seed)

Method Detail

bits

public int bits()

Description copied from interface: HashFunction

Returns the number of bits (a multiple of 32) that each hash code produced by this hash function has.

Specified by:

bits in interface HashFunction

newHasher

public Hasher newHasher()

Description copied from interface: HashFunction

Begins a new hash code computation by returning an initialized, stateful Hasher instance that is ready to receive data. Example:

   

   HashFunction hf = Hashing.md5();
   HashCode hc = hf.newHasher()
       .putLong(id)
       .putBoolean(isActive)
       .hash();

Specified by:

newHasher in interface HashFunction

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

equals

public boolean equals(@Nullable
                      java.lang.Object object)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

hashInt

public HashCode hashInt(int input)

Description copied from interface: HashFunction

Shortcut for newHasher().putInt(input).hash(); returns the hash code for the given int value, interpreted in little-endian byte order. The implementation might perform better than its longhand equivalent, but should not perform worse.

Specified by:

hashInt in interface HashFunction

Overrides:

hashInt in class AbstractStreamingHashFunction

hashLong

public HashCode hashLong(long input)

Description copied from interface: HashFunction

Shortcut for newHasher().putLong(input).hash(); returns the hash code for the given long value, interpreted in little-endian byte order. The implementation might perform better than its longhand equivalent, but should not perform worse.

Specified by:

hashLong in interface HashFunction

Overrides:

hashLong in class AbstractStreamingHashFunction

hashUnencodedChars

public HashCode hashUnencodedChars(java.lang.CharSequence input)

Description copied from interface: HashFunction

Shortcut for newHasher().putUnencodedChars(input).hash(). The implementation might perform better than its longhand equivalent, but should not perform worse. Note that no character encoding is performed; the low byte and high byte of each char are hashed directly (in that order).

Warning: This method will produce different output than most other languages do when running the same hash function on the equivalent input. For cross-language compatibility, use HashFunction.hashString(java.lang.CharSequence, java.nio.charset.Charset), usually with a charset of UTF-8. For other use cases, use hashUnencodedChars.

Specified by:

hashUnencodedChars in interface HashFunction

Overrides:

hashUnencodedChars in class AbstractStreamingHashFunction

mixK1

private static int mixK1(int k1)

mixH1

private static int mixH1(int h1,
                         int k1)

fmix

private static HashCode fmix(int h1,
                             int length)