字节到整形的转换

 public byte[] intToByte(int i) {
        byte[] abyte0 = new byte[4];
        abyte0[0] = (byte) (0xff & i);
        abyte0[1] = (byte) ((0xff00 & i) >> 8);
        abyte0[2] = (byte) ((0xff0000 & i) >> 16);
        abyte0[3] = (byte) ((0xff000000 & i) >> 24);
        return abyte0;
    }



高位在后

    public  static int bytesToInt(byte[] bytes) {
        int addr = bytes[0] & 0xFF;
        addr |= ((bytes[1] << 8) & 0xFF00);
        addr |= ((bytes[2] << 16) & 0xFF0000);
        addr |= ((bytes[3] << 24) & 0xFF000000);
        return addr;
    }