Class FourBitAsciiCompressor

java.lang.Object
com.dannemann.stringcompressor.AsciiCompressor
com.dannemann.stringcompressor.FourBitAsciiCompressor

public class FourBitAsciiCompressor extends AsciiCompressor

Performs 4-bit-per-ASCII-character encoding and decoding.

Compression rate: 50%

  • Field Details

    • DEFAULT_4BIT_CHARSET

      public static final byte[] DEFAULT_4BIT_CHARSET
  • Constructor Details

    • FourBitAsciiCompressor

      public FourBitAsciiCompressor()
    • FourBitAsciiCompressor

      public FourBitAsciiCompressor(byte[] supportedCharset)
    • FourBitAsciiCompressor

      public FourBitAsciiCompressor(boolean throwException)
  • Method Details

    • compress

      public final byte[] compress(byte[] str)

      Compresses 2 characters into 1 byte (4 bits each). Supports a set of 16 different characters (0000 to 1111).

      Compression rate: 50%

      See DEFAULT_4BIT_CHARSET for the default set of supported characters.

      Specified by:
      compress in class AsciiCompressor
      Parameters:
      str - String to be compressed.
      Returns:
      A compressed byte array.
    • decompress

      public final byte[] decompress(byte[] compressed)
      Restores the original string from data compressed by AsciiCompressor.compress(byte[]).
      Specified by:
      decompress in class AsciiCompressor
      Parameters:
      compressed - The compressed string byte array.
      Returns:
      A decompressed string byte array.
    • validateSupportedCharset

      protected void validateSupportedCharset(byte[] supportedCharset)
      Specified by:
      validateSupportedCharset in class AsciiCompressor