bytesToHex 求哈希

bytesToHex

byte[] 和 Hex 字符串相互轉換

public class Util {

    private final static char[] hexArray = "0123456789ABCDEF".toCharArray();

    //Original source: https://stackoverflow.com/a/9855338/1389357
    public static String bytesToHex(byte[] bytes) {
        char[] hexChars = new char[bytes.length * 2];
        for ( int j = 0; j < bytes.length; j++ ) {
            int v = bytes[j] & 0xFF;
            hexChars[j * 2] = hexArray[v >>> 4];
            hexChars[j * 2 + 1] = hexArray[v & 0x0F];
        }
        return new String(hexChars);
    }

    public static byte[] hexStrToByteArray(String str)
    {
        if (str == null) {
            return null;
        }
        if (str.length() == 0) {
            return new byte[0];
        }
        byte[] byteArray = new byte[str.length() / 2];
        for (int i = 0; i < byteArray.length; i++){
            String subStr = str.substring(2 * i, 2 * i + 2);
            byteArray[i] = ((byte)Integer.parseInt(subStr, 16));
        }
        return byteArray;
    }

}