Package org.tribuo.hash

Class MessageDigestHasher

java.lang.Object

org.tribuo.hash.Hasher

org.tribuo.hash.MessageDigestHasher

All Implemented Interfaces:

com.oracle.labs.mlrg.olcut.config.Configurable, com.oracle.labs.mlrg.olcut.provenance.Provenancable<com.oracle.labs.mlrg.olcut.provenance.ConfiguredObjectProvenance>, Serializable, ProtoSerializable<org.tribuo.protos.core.HasherProto>

public final class MessageDigestHasher
extends Hasher

Hashes Strings using the supplied MessageDigest type.

MessageDigestHasher does not serialize the salt in its serialized forms, and thus the salt must be set after deserialization.

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	MessageDigestHasher.MessageDigestHasherProvenance	Provenance for MessageDigestHasher.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	CURRENT_VERSION	Protobuf serialization version.
static final Charset	utf8Charset	Alias for StandardCharsets.UTF_8.

Fields inherited from class org.tribuo.hash.Hasher

MIN_LENGTH

Fields inherited from interface org.tribuo.protos.ProtoSerializable

DESERIALIZATION_METHOD_NAME, PROVENANCE_SERIALIZER

Constructor Summary

Constructors

Constructor	Description
MessageDigestHasher(String hashType, String salt)	Constructs a message digest hasher.

Method Summary

Modifier and Type	Method	Description
static MessageDigestHasher	deserializeFromProto(int version, String className, com.google.protobuf.Any message)	Deserialization factory.
boolean	equals(Object o)
static Supplier<MessageDigest>	getDigestSupplier(String hashType)	Creates a supplier for the specified hash type.
com.oracle.labs.mlrg.olcut.provenance.ConfiguredObjectProvenance	getProvenance()
String	hash(String input)	Hashes the supplied input using the hashing function.
int	hashCode()
void	postConfig()	Used by the OLCUT configuration system, and should not be called by external code.
org.tribuo.protos.core.HasherProto	serialize()	Serializes this object to a protobuf.
void	setSalt(String salt)	The salt is transient, it must be set **to the same value as it was trained with** after the Model is deserialized.
String	toString()

Methods inherited from class org.tribuo.hash.Hasher

validateSalt

Methods inherited from class java.lang.Object

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

Field Details

CURRENT_VERSION

public static final int CURRENT_VERSION

Protobuf serialization version.

See Also:

• Constant Field Values

utf8Charset

public static final Charset utf8Charset

Alias for StandardCharsets.UTF_8.

Constructor Details

MessageDigestHasher

public MessageDigestHasher(String hashType,
 String salt)

Constructs a message digest hasher.

Parameters:

hashType - The hash function to use.

salt - The salt value.

Method Details

deserializeFromProto

public static MessageDigestHasher deserializeFromProto(int version,
 String className,
 com.google.protobuf.Any message)
                                                throws com.google.protobuf.InvalidProtocolBufferException

Deserialization factory.

Note the salt must be set after the hasher has been deserialized.

Parameters:

version - The serialized object version number.

className - The class name.

message - The serialized data.

Returns:

The deserialized object.

Throws:

com.google.protobuf.InvalidProtocolBufferException - If the protobuf could not be parsed from the message.

postConfig

public void postConfig()
                throws com.oracle.labs.mlrg.olcut.config.PropertyException

Used by the OLCUT configuration system, and should not be called by external code.

Throws:

com.oracle.labs.mlrg.olcut.config.PropertyException

hash

public String hash(String input)

Description copied from class: Hasher

Hashes the supplied input using the hashing function.

If the salt is not set then this throws IllegalStateException.

Specified by:

hash in class Hasher

Parameters:

input - The input to hash.

Returns:

A String representation of the hashed output.

serialize

public org.tribuo.protos.core.HasherProto serialize()

Description copied from interface: ProtoSerializable

Serializes this object to a protobuf.

Returns:

The protobuf.

setSalt

public void setSalt(String salt)

Description copied from class: Hasher

The salt is transient, it must be set **to the same value as it was trained with** after the Model is deserialized.

Specified by:

setSalt in class Hasher

Parameters:

salt - Salt value.

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

getProvenance

public com.oracle.labs.mlrg.olcut.provenance.ConfiguredObjectProvenance getProvenance()

getDigestSupplier

public static Supplier<MessageDigest> getDigestSupplier(String hashType)

Creates a supplier for the specified hash type.

Parameters:

hashType - The hash type, used to specify the MessageDigest implementation.

Returns:

A supplier for the MessageDigest.