Package org.bouncycastle.crypto.digests

Class ShortenedDigest

  • All Implemented Interfaces:
    Digest, ExtendedDigest
    public class ShortenedDigest
extends java.lang.Object
implements ExtendedDigest
    Wrapper class that reduces the output length of a particular digest to only the first n bytes of the digest function.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int doFinal​(byte[] out, int outOff)
      close the digest, producing the final digest value.
      java.lang.String getAlgorithmName()
      return the algorithm name
      int getByteLength()
      Return the size in bytes of the internal buffer the digest applies it's compression function to.
      int getDigestSize()
      return the size, in bytes, of the digest produced by this message digest.
      void reset()
      reset the digest back to it's initial state.
      void update​(byte in)
      update the message digest with a single byte.
      void update​(byte[] in, int inOff, int len)
      update the message digest with a block of bytes.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • ShortenedDigest

        public ShortenedDigest​(ExtendedDigest baseDigest,
                       int length)
        Base constructor.
        Parameters:
        baseDigest - underlying digest to use.
        length - length in bytes of the output of doFinal.
        Throws:
        java.lang.IllegalArgumentException - if baseDigest is null, or length is greater than baseDigest.getDigestSize().

    • Method Detail

      • getAlgorithmName

        public java.lang.String getAlgorithmName()
        Description copied from interface: Digest
        return the algorithm name
        Specified by:
        getAlgorithmName in interface Digest
        Returns:
        the algorithm name

      • getDigestSize

        public int getDigestSize()
        Description copied from interface: Digest
        return the size, in bytes, of the digest produced by this message digest.
        Specified by:
        getDigestSize in interface Digest
        Returns:
        the size, in bytes, of the digest produced by this message digest.

      • update

        public void update​(byte in)
        Description copied from interface: Digest
        update the message digest with a single byte.
        Specified by:
        update in interface Digest
        Parameters:
        in - the input byte to be entered.

      • update

        public void update​(byte[] in,
                   int inOff,
                   int len)
        Description copied from interface: Digest
        update the message digest with a block of bytes.
        Specified by:
        update in interface Digest
        Parameters:
        in - the byte array containing the data.
        inOff - the offset into the byte array where the data starts.
        len - the length of the data.

      • doFinal

        public int doFinal​(byte[] out,
                   int outOff)
        Description copied from interface: Digest
        close the digest, producing the final digest value. The doFinal call leaves the digest reset.
        Specified by:
        doFinal in interface Digest
        Parameters:
        out - the array the digest is to be copied into.
        outOff - the offset into the out array the digest is to start at.

      • reset

        public void reset()
        Description copied from interface: Digest
        reset the digest back to it's initial state.
        Specified by:
        reset in interface Digest

      • getByteLength

        public int getByteLength()
        Description copied from interface: ExtendedDigest
        Return the size in bytes of the internal buffer the digest applies it's compression function to.
        Specified by:
        getByteLength in interface ExtendedDigest
        Returns:
        byte length of the digests internal buffer.