Class AbstractHashFunction

java.lang.Object
com.google.common.hash.AbstractHashFunction
All Implemented Interfaces:
HashFunction
Direct Known Subclasses:
AbstractCompositeHashFunction, AbstractNonStreamingHashFunction, ChecksumHashFunction, Crc32cHashFunction, MacHashFunction, MessageDigestHashFunction, Murmur3_128HashFunction, Murmur3_32HashFunction, SipHashFunction

abstract class AbstractHashFunction extends Object implements HashFunction
Skeleton implementation of HashFunction in terms of HashFunction.newHasher().

TODO(lowasser): make public

  • Constructor Details

    • AbstractHashFunction

      AbstractHashFunction()
  • Method Details

    • hashObject

      public <T> HashCode hashObject(T instance, Funnel<? super T> funnel)
      Description copied from interface: HashFunction
      Shortcut for newHasher().putObject(instance, funnel).hash(). The implementation might perform better than its longhand equivalent, but should not perform worse.
      Specified by:
      hashObject in interface HashFunction
    • hashUnencodedChars

      public HashCode hashUnencodedChars(CharSequence input)
      Description copied from interface: HashFunction
      Shortcut for newHasher().putUnencodedChars(input).hash(). The implementation might perform better than its longhand equivalent, but should not perform worse. Note that no character encoding is performed; the low byte and high byte of each char are hashed directly (in that order).

      Warning: This method will produce different output than most other languages do when running the same hash function on the equivalent input. For cross-language compatibility, use HashFunction.hashString(java.lang.CharSequence, java.nio.charset.Charset), usually with a charset of UTF-8. For other use cases, use hashUnencodedChars.

      Specified by:
      hashUnencodedChars in interface HashFunction
    • hashString

      public HashCode hashString(CharSequence input, Charset charset)
      Description copied from interface: HashFunction
      Shortcut for newHasher().putString(input, charset).hash(). Characters are encoded using the given Charset. The implementation might perform better than its longhand equivalent, but should not perform worse.

      Warning: This method, which reencodes the input before hashing it, is useful only for cross-language compatibility. For other use cases, prefer HashFunction.hashUnencodedChars(java.lang.CharSequence), which is faster, produces the same output across Java releases, and hashes every char in the input, even if some are invalid.

      Specified by:
      hashString in interface HashFunction
    • hashInt

      public HashCode hashInt(int input)
      Description copied from interface: HashFunction
      Shortcut for newHasher().putInt(input).hash(); returns the hash code for the given int value, interpreted in little-endian byte order. The implementation might perform better than its longhand equivalent, but should not perform worse.
      Specified by:
      hashInt in interface HashFunction
    • hashLong

      public HashCode hashLong(long input)
      Description copied from interface: HashFunction
      Shortcut for newHasher().putLong(input).hash(); returns the hash code for the given long value, interpreted in little-endian byte order. The implementation might perform better than its longhand equivalent, but should not perform worse.
      Specified by:
      hashLong in interface HashFunction
    • hashBytes

      public HashCode hashBytes(byte[] input)
      Description copied from interface: HashFunction
      Shortcut for newHasher().putBytes(input).hash(). The implementation might perform better than its longhand equivalent, but should not perform worse.
      Specified by:
      hashBytes in interface HashFunction
    • hashBytes

      public HashCode hashBytes(byte[] input, int off, int len)
      Description copied from interface: HashFunction
      Shortcut for newHasher().putBytes(input, off, len).hash(). The implementation might perform better than its longhand equivalent, but should not perform worse.
      Specified by:
      hashBytes in interface HashFunction
    • hashBytes

      public HashCode hashBytes(ByteBuffer input)
      Description copied from interface: HashFunction
      Shortcut for newHasher().putBytes(input).hash(). The implementation might perform better than its longhand equivalent, but should not perform worse.
      Specified by:
      hashBytes in interface HashFunction
    • newHasher

      public Hasher newHasher(int expectedInputSize)
      Description copied from interface: HashFunction
      Begins a new hash code computation as HashFunction.newHasher(), but provides a hint of the expected size of the input (in bytes). This is only important for non-streaming hash functions (hash functions that need to buffer their whole input before processing any of it).
      Specified by:
      newHasher in interface HashFunction