code: public void addMapping( byte[] src, String dest ) throws IOException
      {
          if( src.length == 1 )
          {
          	singleByteMappings.put( Integer.valueOf( src[0] & 0xff ), dest );
          }
          else if( src.length == 2 )
          {
              int intSrc = src[0]&0xFF;
              intSrc <<= 8;
              intSrc |= (src[1]&0xFF);
              doubleByteMappings.put( Integer.valueOf( intSrc ), dest );
          }
          else
          {
              throw new IOException( "Mapping code should be 1 or two bytes and not " + src.length );
          }
      }
docs: This will add a mapping.
  
  @param src The src to the mapping.
  @param dest The dest to the mapping.
  
  @throws IOException if the src is invalid.