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一个使用位运算实现的简单的字符串对称加密工具

public class StringCrypto {
    public static void main(String[] args) {
        String test = "hello hello";
        String key = "hellohello";
        String code = crypto(test, key);
        String recode = deCrypto(code, key);
        System.out.println(code);
        System.out.println(recode);
    }

    public static String crypto(String resource, String key){
        byte[] bs = resource.getBytes(Consts.UTF_8);
        byte[] kbs = key.getBytes(Consts.UTF_8);
        StringBuilder builder = new StringBuilder("1");
        for (int i = 0; i <bs.length; i++) {
            int temp = bs[i]+kbs[i%kbs.length]+256;
            builder.append(String.format("%3d",Math.abs(temp)).replace(\' \',\'0\'));
        }
        BigInteger bigInteger = new BigInteger(builder.toString(),10);
        return bigInteger.toString(36);
    }

    public static String deCrypto(String code, String key){
        byte[] kbs = key.getBytes(Consts.UTF_8);
        BigInteger bigInteger = new BigInteger(code, 36);
        String source = bigInteger.toString(10);
        int len = source.length()/3;
        byte[] bs = new byte[len];
        for (int i = 0; i < bs.length; i++) {
            int temp = Integer.parseInt(source.substring(3*i+1, 3*(i+1)+1));
            bs[i] = (byte)(temp - kbs[i%kbs.length]-256);
        }
        return new String(bs,Consts.UTF_8);
    }
}