【资料分享】Android NFC通信例子

1万 · 2014-3-22 12:20

/* NFCard is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.

NFCard is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

Additional permission under GNU GPL version 3 section 7 */

package com.sinpo.xnfc;

public final class Util {
private final static char[] HEX = { '0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

private Util() {
}

public static byte[] toBytes(int a) {
return new byte[] { (byte) (0x000000ff & (a >>> 24)),
(byte) (0x000000ff & (a >>> 16)),
(byte) (0x000000ff & (a >>> 8)), (byte) (0x000000ff & (a)) };
}

public static int toInt(byte[] b, int s, int n) {
int ret = 0;

final int e = s + n;
for (int i = s; i < e; ++i) {
ret <<= 8;
ret |= b[i] & 0xFF;
}
return ret;
}

public static String toHexStringR(byte[] d, int s, int n) {
final char[] ret = new char[n * 2];

int x = 0;
for (int i = s + n - 1; i >= s; --i) {
final byte v = d[i];
ret[x++] = HEX[0x0F & (v >> 4)];
ret[x++] = HEX[0x0F & v];
}
return new String(ret);
}

}