Package com.scurrilous.circe.impl

Class IntStatefulLongHash

java.lang.Object

com.scurrilous.circe.impl.IntStatefulLongHash

All Implemented Interfaces:

Hash, StatefulHash, StatefulLongHash

public final class IntStatefulLongHash
extends java.lang.Object
implements StatefulLongHash

Promotes a StatefulIntHash to a StatefulLongHash.

Constructor Summary

Constructors

Constructor	Description
IntStatefulLongHash(StatefulIntHash intHash)	Constructs a new IntStatefulLongHash that delegates to the given StatefulIntHash.

Method Summary

Modifier and Type	Method	Description
java.lang.String	algorithm()	Returns the canonical name of this hash algorithm.
StatelessLongHash	asStateless()	Returns an instance of stateless version of this hash function.
StatefulHash	createNew()	Returns a new instance of this stateful hash function reset to the initial state.
byte	getByte()	Returns the first byte of the output of this hash function.
byte[]	getBytes()	Returns a new byte array containing the output of this hash function.
int	getBytes(byte[] output, int index, int maxLength)	Writes the output of this hash function into the given byte array at the given offset.
int	getInt()	Returns the first four bytes of the output of this hash function as a little-endian int.
long	getLong()	Returns the first eight bytes of the output of this hash function as a little-endian long.
short	getShort()	Returns the first two bytes of the output of this hash function as a little-endian short.
int	length()	Returns the length in bytes of the output of this hash function.
void	reset()	Resets this hash function to its initial state.
boolean	supportsIncremental()	Returns whether this hash function supports incremental hashing.
boolean	supportsUnsafe()	Returns whether this hash function supports unsafe access to arbitrary memory addresses using methods such as StatefulHash.update(long, long), StatelessIntHash.calculate(long, long), or IncrementalIntHash.resume(int, long, long).
void	update(byte[] input)	Updates the state of this hash function with the entire given input array.
void	update(byte[] input, int index, int length)	Updates the state of this hash function with the given range of the given input array.
void	update(long address, long length)	Updates the state of this hash function with memory with the given address and length.
void	update(java.nio.ByteBuffer input)	Updates the state of this hash function with the remaining contents of the given input buffer.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

IntStatefulLongHash

public IntStatefulLongHash(StatefulIntHash intHash)

Constructs a new IntStatefulLongHash that delegates to the given StatefulIntHash.

Parameters:

intHash - the underlying int-width hash

Method Detail

asStateless

public StatelessLongHash asStateless()

Description copied from interface: StatefulLongHash

Returns an instance of stateless version of this hash function.

Specified by:

asStateless in interface StatefulLongHash

Returns:

the stateless version of this hash function

algorithm

public java.lang.String algorithm()

Description copied from interface: Hash

Returns the canonical name of this hash algorithm.

Specified by:

algorithm in interface Hash

Returns:

the name of this hash algorithm

length

public int length()

Description copied from interface: Hash

Returns the length in bytes of the output of this hash function.

Specified by:

length in interface Hash

Returns:

the hash length in bytes

createNew

public StatefulHash createNew()

Description copied from interface: StatefulHash

Returns a new instance of this stateful hash function reset to the initial state.

Specified by:

createNew in interface StatefulHash

Returns:

a new instance of this hash in the initial state

supportsUnsafe

public boolean supportsUnsafe()

Description copied from interface: Hash

Returns whether this hash function supports unsafe access to arbitrary memory addresses using methods such as StatefulHash.update(long, long), StatelessIntHash.calculate(long, long), or IncrementalIntHash.resume(int, long, long). Such functions are generally implemented in native code.

Specified by:

supportsUnsafe in interface Hash

Returns:

true if unsafe access is supported, false if not

supportsIncremental

public boolean supportsIncremental()

Description copied from interface: StatefulHash

Returns whether this hash function supports incremental hashing. Incremental hashing allows calling the StatefulHash.update(byte[]) methods to continue hashing using accumulated state after calling any of the output methods (such as StatefulHash.getBytes()). Non-incremental hash functions require calling StatefulHash.reset() to reinitialize the state between calling an output method and an update method.

Specified by:

supportsIncremental in interface StatefulHash

Returns:

true if incremental hashing is supported, false if not

reset

public void reset()

Description copied from interface: StatefulHash

Resets this hash function to its initial state. Resetting the state is required for non-incremental hash functions after any output methods have been called.

Specified by:

reset in interface StatefulHash

update

public void update(byte[] input)

Description copied from interface: StatefulHash

Updates the state of this hash function with the entire given input array.

Specified by:

update in interface StatefulHash

Parameters:

input - the input array

update

public void update(byte[] input,
                   int index,
                   int length)

Description copied from interface: StatefulHash

Updates the state of this hash function with the given range of the given input array.

Specified by:

update in interface StatefulHash

Parameters:

input - the input array

index - the starting index of the first input byte

length - the length of the input range

update

public void update(java.nio.ByteBuffer input)

Description copied from interface: StatefulHash

Updates the state of this hash function with the remaining contents of the given input buffer. This method leaves the buffer position at the limit.

Specified by:

update in interface StatefulHash

Parameters:

input - the input buffer

update

public void update(long address,
                   long length)

Description copied from interface: StatefulHash

Updates the state of this hash function with memory with the given address and length. The arguments are generally not checked in any way and will likely lead to a VM crash or undefined results if invalid.

Specified by:

update in interface StatefulHash

Parameters:

address - the base address of the input

length - the length of the input

See Also:

Hash.supportsUnsafe()

getBytes

public byte[] getBytes()

Description copied from interface: StatefulHash

Returns a new byte array containing the output of this hash function. The caller may freely modify the contents of the array.

Specified by:

getBytes in interface StatefulHash

Returns:

a new byte array containing the hash output

getBytes

public int getBytes(byte[] output,
                    int index,
                    int maxLength)

Description copied from interface: StatefulHash

Writes the output of this hash function into the given byte array at the given offset.

Specified by:

getBytes in interface StatefulHash

Parameters:

output - the destination array for the output

index - the starting index of the first output byte

maxLength - the maximum number of bytes to write

Returns:

the number of bytes written

getByte

public byte getByte()

Description copied from interface: StatefulHash

Returns the first byte of the output of this hash function.

Specified by:

getByte in interface StatefulHash

Returns:

the first output byte

getShort

public short getShort()

Description copied from interface: StatefulHash

Returns the first two bytes of the output of this hash function as a little-endian short. If the output is less than two bytes, the remaining bytes are set to 0.

Specified by:

getShort in interface StatefulHash

Returns:

the first two output bytes as a short

getInt

public int getInt()

Description copied from interface: StatefulHash

Returns the first four bytes of the output of this hash function as a little-endian int. If the output is less than four bytes, the remaining bytes are set to 0.

Specified by:

getInt in interface StatefulHash

Returns:

the first four output bytes as an int

getLong

public long getLong()

Description copied from interface: StatefulHash

Returns the first eight bytes of the output of this hash function as a little-endian long. If the output is less than eight bytes, the remaining bytes are set to 0.

Specified by:

getLong in interface StatefulHash

Returns:

the first eight output bytes as a long