Android 蓝牙(Bluetooth)

算法 → byte数组 和 16进制进制见的转换

http://javaman.group.iteye.com/group/wiki/3405-cuisuqiang-google-socket-InputStream-OutputStream

private final static byte[] hex = "0123456789ABCDEF".getBytes();

private static int parse(char c) {
    if (c >= ‘a‘)
        return (c - ‘a‘ + 10) & 0x0f;
    if (c >= ‘A‘)
        return (c - ‘A‘ + 10) & 0x0f;
    return (c - ‘0‘) & 0x0f;
}
// 从字节数组到十六进制字符串转换
public static String Bytes2HexString(byte[] b) {
    byte[] buff = new byte[2 * b.length];
    for (int i = 0; i < b.length; i++) {
        buff[2 * i] = hex[(b[i] >> 4) & 0x0f];
        buff[2 * i + 1] = hex[b[i] & 0x0f];
    }
    return new String(buff);
}

// 从十六进制字符串到字节数组转换
public static byte[] HexString2Bytes(String hexstr) {
    byte[] b = new byte[hexstr.length() / 2];
    int j = 0;
    for (int i = 0; i < b.length; i++) {
        char c0 = hexstr.charAt(j++);
        char c1 = hexstr.charAt(j++);
        b[i] = (byte) ((parse(c0) << 4) | parse(c1));
    }
    return b;
}

public static void main(String[] args) {
    byte[] bt = new byte[]{10, 2, 12, 14, 1, 0, 0, 1, 0, 31, 45, 1, 8, 0, 1, 0, -96, -45, 10, 3};
    System.out.println(Bytes2HexString(bt));
    System.out.println(Arrays.toString(HexString2Bytes("0A020C0E01000001001F2D0108000100A0D30A03")));
}

打印

0A020C0E01000001001F2D0108000100A0D30A03
[10, 2, 12, 14, 1, 0, 0, 1, 0, 31, 45, 1, 8, 0, 1, 0, -96, -45, 10, 3]

// 返回无符号的2进制表示 1110011
String hex = Integer.toBinaryString(115);
System.out.println(hex);
// 返回2进制的字符串1110011对应的值 115
System.out.println(Integer.valueOf("1110011", 2));

// 16进制值转换成二进制
System.out.println(Long.parseLong("49", 16));
System.out.println(Long.parseLong("2F", 16));