Package com.scurrilous.circe.impl

Class AbstractIncrementalLongHash

java.lang.Object
com.scurrilous.circe.impl.AbstractIncrementalLongHash
All Implemented Interfaces:
Hash, IncrementalLongHash, StatelessHash, StatelessLongHash
Direct Known Subclasses:
AbstractLongCrc
public abstract class AbstractIncrementalLongHash extends Object implements IncrementalLongHash
Base implementation for incremental stateless long integer hash functions.

  • Constructor Summary

    Constructors
    Constructor
    Description
    AbstractIncrementalLongHash()
     

  • 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(ByteBuffer input)
    Evaluates this hash function with the remaining contents of the given input buffer.
    StatefulLongHash
    createStateful()
    Returns a new instance of stateful version of this hash function.
    protected abstract long
    initial()
    The initial state of the hash function, which is the same as the output value for an empty input sequence.
    long
    resume(long current, byte[] input)
    Evaluates this hash function as if the entire given input array were appended to the previously hashed input.
    long
    resume(long current, byte[] input, int index, int length)
    Evaluates this hash function as if the given range of the given input array were appended to the previously hashed input.
    long
    resume(long current, long address, long length)
    Evaluates this hash function as if the memory with the given address and length were appended to the previously hashed input.
    long
    resume(long current, ByteBuffer input)
    Evaluates this hash function as if the remaining contents of the given input buffer were appended to the previously hashed input.
    protected abstract long
    resumeUnchecked(long current, byte[] input, int index, int length)
    Evaluates this hash function as if the given range of the given input array were appended to the previously hashed input.
    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

  • Constructor Details

    • AbstractIncrementalLongHash

      public AbstractIncrementalLongHash()

  • Method Details

    • 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

    • createStateful

      public StatefulLongHash createStateful()
      Description copied from interface: StatelessLongHash
      Returns a new instance of stateful version of this hash function.
      Specified by:
      createStateful in interface StatelessHash
      Specified by:
      createStateful in interface StatelessLongHash
      Returns:
      the stateful version of this hash function

    • 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(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:

    • resume

      public long resume(long current, byte[] input)
      Description copied from interface: IncrementalLongHash
      Evaluates this hash function as if the entire given input array were appended to the previously hashed input.
      Specified by:
      resume in interface IncrementalLongHash
      Parameters:
      current - the hash output for input hashed so far
      input - the input array
      Returns:
      the output of the hash function for the concatenated input

    • resume

      public long resume(long current, byte[] input, int index, int length)
      Description copied from interface: IncrementalLongHash
      Evaluates this hash function as if the given range of the given input array were appended to the previously hashed input.
      Specified by:
      resume in interface IncrementalLongHash
      Parameters:
      current - the hash output for input hashed so far
      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 for the concatenated input

    • resume

      public long resume(long current, ByteBuffer input)
      Description copied from interface: IncrementalLongHash
      Evaluates this hash function as if the remaining contents of the given input buffer were appended to the previously hashed input. This method leaves the buffer position at the limit.
      Specified by:
      resume in interface IncrementalLongHash
      Parameters:
      current - the hash output for input hashed so far
      input - the input buffer
      Returns:
      the output of the hash function for the concatenated input

    • resume

      public long resume(long current, long address, long length)
      Description copied from interface: IncrementalLongHash
      Evaluates this hash function as if the memory with the given address and length were appended to the previously hashed input. The arguments are generally not checked in any way and will likely lead to a VM crash or undefined results if invalid.
      Specified by:
      resume in interface IncrementalLongHash
      Parameters:
      current - the hash output for input hashed so far
      address - the base address of the input
      length - the length of the input
      Returns:
      the output of the hash function for the concatenated input
      See Also:

    • initial

      protected abstract long initial()
      The initial state of the hash function, which is the same as the output value for an empty input sequence.
      Returns:
      the initial hash state/output

    • resumeUnchecked

      protected abstract long resumeUnchecked(long current, byte[] input, int index, int length)
      Evaluates this hash function as if the given range of the given input array were appended to the previously hashed input. The index and length parameters have already been validated.
      Parameters:
      current - the hash output for input hashed so far
      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 for the concatenated input