Package com.scurrilous.circe

Interface IncrementalIntHash

All Superinterfaces:
Hash, StatelessHash, StatelessIntHash
All Known Implementing Classes:
AbstractIncrementalIntHash, AbstractIntCrc, NormalByteCrc, NormalIntCrc, ReflectedIntCrc, Sse42Crc32C
public interface IncrementalIntHash extends StatelessIntHash
Incremental stateless integer hash function, which has the property that its output is the same as (or easily derivable from) its state. Specifically, for any sequence M partitioned arbitrarily into two subsequences M1 M2: 
 h(M) = h'(h(M1), M2)
where h corresponds to the calculate function and h' corresponds to the resume(int, byte[]) function.

Note that stateful hash functions obtained from incremental stateless hash functions are also incremental.

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    resume(int current, byte[] input)
    Evaluates this hash function as if the entire given input array were appended to the previously hashed input.
    int
    resume(int 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.
    int
    resume(int 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.
    int
    resume(int current, ByteBuffer input)
    Evaluates this hash function as if the remaining contents of the given input buffer were appended to the previously hashed input.

    Methods inherited from interface com.scurrilous.circe.Hash

    algorithm, length, supportsUnsafe

    Methods inherited from interface com.scurrilous.circe.StatelessIntHash

    calculate, calculate, calculate, calculate, createStateful

  • Method Details

    • resume

      int resume(int current, byte[] input)
      Evaluates this hash function as if the entire given input array were appended to the previously hashed input.
      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

      int resume(int 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.
      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
      Throws:
      IndexOutOfBoundsException - if index is negative or index + length is greater than the array length

    • resume

      int resume(int current, ByteBuffer input)
      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.
      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

      int resume(int 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. The arguments are generally not checked in any way and will likely lead to a VM crash or undefined results if invalid.
      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
      Throws:
      UnsupportedOperationException - if this function does not support unsafe memory access
      See Also: