Package com.scurrilous.circe.impl

Class AbstractStatelessLongHash

java.lang.Object

com.scurrilous.circe.impl.AbstractStatelessLongHash

All Implemented Interfaces:

Hash, StatelessHash, StatelessLongHash

public abstract class AbstractStatelessLongHash
extends java.lang.Object
implements StatelessLongHash

Base implementation for stateless (but not incremental) long integer hash functions.

Constructor Summary

Constructors

Constructor	Description
AbstractStatelessLongHash()

Method Summary

Modifier and Type	Method	Description
long	calculate(byte[] input)	Evaluates this hash function for the entire given input array.
long	calculate(byte[] input, int index, int length)	Evaluates this hash function for the given range of the given input array.
long	calculate(long address, long length)	Evaluates this hash function for the memory with the given address and length.
long	calculate(java.nio.ByteBuffer input)	Evaluates this hash function with the remaining contents of the given input buffer.
protected abstract long	calculateUnchecked(byte[] input, int index, int length)	Evaluates this hash function for the given range of the given input array.
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).

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.scurrilous.circe.Hash

algorithm, length

Methods inherited from interface com.scurrilous.circe.StatelessLongHash

createStateful

Constructor Detail

AbstractStatelessLongHash

public AbstractStatelessLongHash()

Method Detail

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

calculate

public long calculate(byte[] input)

Description copied from interface: StatelessLongHash

Evaluates this hash function for the entire given input array.

Specified by:

calculate in interface StatelessLongHash

Parameters:

input - the input array

Returns:

the output of the hash function

calculate

public long calculate(byte[] input,
                      int index,
                      int length)

Description copied from interface: StatelessLongHash

Evaluates this hash function for the given range of the given input array.

Specified by:

calculate in interface StatelessLongHash

Parameters:

input - the input array

index - the starting index of the first input byte

length - the length of the input range

Returns:

the output of the hash function

calculate

public long calculate(java.nio.ByteBuffer input)

Description copied from interface: StatelessLongHash

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

Specified by:

calculate in interface StatelessLongHash

Parameters:

input - the input buffer

Returns:

the output of the hash function

calculate

public long calculate(long address,
                      long length)

Description copied from interface: StatelessLongHash

Evaluates this hash function for the 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:

calculate in interface StatelessLongHash

Parameters:

address - the base address of the input

length - the length of the input

Returns:

the output of the hash function

See Also:

Hash.supportsUnsafe()

calculateUnchecked

protected abstract long calculateUnchecked(byte[] input,
                                           int index,
                                           int length)

Evaluates this hash function for the given range of the given input array. The index and length parameters have already been validated.

Parameters:

input - the input array

index - the starting index of the first input byte

length - the length of the input range

Returns:

the output of the hash function