public static String byte2Hex(int value){
  if (value > 255 || value < 0) {
    throw new IllegalArgumentException("The int converting to hex should be in range 0~255");
  }
  return String.valueOf(FIRST_CHAR[value]) + String.valueOf(SECOND_CHAR[value]);
}

public static String byte2Hex ( int value ) { if ( value > 255 || value < 0 ) { throw new IllegalArgumentException ( "The int converting to hex should be in range 0~255" ) ; } return String . valueOf ( FIRST_CHAR [ value ] ) + String . valueOf ( SECOND_CHAR [ value ] ) ; }
convert an int [ 0 - 255 ] to a hexadecimal string representation .
