文字列とbyte配列の相互変換

public static String getHexString(byte[] b) throws Exception {

  String result = "";

  for (int i=0; i < b.length; i++) {

    result += Integer.toString( ( b[i] & 0xff ) + 0x100, 16).substring( 1 );

  }

  return result;

}

 

public static byte[] getByteArray(String hexString) {

  return new BigInteger(hexString,16).toByteArray(); 

}

1 String str = "Hello";

2 byte[] srtbyte = str.getBytes();// 

3 // byte[]   string

4 String res = new String(srtbyte);

5 System.out.println(res);