Question

我正在写一个Vigenere密码。它适用于普通的char，但是当我在Mac键盘上使用额外的char（例如使用选项和c）时，它会中断。是因为它超出了char范围吗？

Output using read byte individually
hello testing long output!@#)!(!*!(@()asdfasdfljkasdfjËÂ©âÃ¥Â¬ÃËââÃ¥ËÃâÃ§ËâËÃ¸ÅËÃÂ¨âÏÃ¥Ã¸Ã
Output using read(byte[])
hello testing long output!@#)!(!*!(@()asdfasdfljkasdfjￋﾙￂﾩ￢ﾈﾆￃﾥￂﾬￃﾟￋﾚ￢ﾈﾂ￢ﾈﾆￃﾥￋﾙￃﾟ￢ﾈﾆￃﾧￋﾆ￢ﾈﾑￋﾆￃﾸￅﾓￋﾆￃﾟￂﾨ￢ﾈﾂￏﾀￃﾥￃﾸￃﾟ

代码：

import java.io.*;

class VigenereFilterInputStream extends FilterInputStream {
    private final byte[] key;
    private int index = 0;

    VigenereFilterInputStream(InputStream in, byte[] k) {
        super(in);
        key = k.clone();
    }

    public int read() throws IOException {
        int c = super.read();

        if (c == -1) 
            return -1;

        int out = c ^ key[index];
        index ++;
        index %= key.length;
        return out;
    }

    public int read(byte[] b) throws IOException {
        int result = in.read(b);
        for(int i = 0; i < b.length; i++) {
            b[i] = (byte) (b[i] ^ key[i % key.length]);
        }
        return result;
    }
}

class VigenereFilterOutputStream extends FilterOutputStream {
    private final byte[] key;

    VigenereFilterOutputStream(OutputStream out, byte[] k) {
        super(out);
        key = k.clone();
    }

    public void write(byte[] b) throws IOException {
        byte[] out = new byte[b.length];

        for(int i = 0; i < b.length; i++) {
            out[i] = (byte) (b[i] ^ key[i % key.length]);
        }
        super.write(out);
    }
}

class Vigenere {
    public static void main(String[] args) throws Exception {
        if (args.length != 1) {
            throw new Exception("Missing filename");
        }

        File f = new File(args[0]);

        byte[] text = "hello testing long output!@#)!(!*!(@()asdfasdfljkasdfj˙©∆å¬ß˚∂∆å˙ß∆çˆ∑ˆøœˆß¨∂πåøß".getBytes();
        byte[] key = "hello".getBytes();

        FileOutputStream os = new FileOutputStream(f);
        VigenereFilterOutputStream encrypt = new VigenereFilterOutputStream(os, key);

        encrypt.write(text);

        FileInputStream is = new FileInputStream(f);
        BufferedInputStream bis = new BufferedInputStream(is);
        VigenereFilterInputStream decrypt = new VigenereFilterInputStream(bis, key);

        bis.mark(text.length);
        int c;
        while((c = decrypt.read()) != -1) {
            System.out.print((char) c);
        }

        System.out.println();

        bis.reset();
        byte[] b = new byte[text.length];
        decrypt.read(b);

        for(byte d: b) {
            System.out.print((char) d);
        }
        System.out.println();
    }
}

Mac OS中的特殊键

0 个答案: