java - 尝试查看转化时出现垃圾邮件

Question

我对这个简单的类有疑问。当我尝试通过凯撒密码转换输入字符串时，我得到的字符串比想象的要多。怎么了？我是否仅对字符串内容正确实现序列化和反序列化？为什么输出是:[C@58a1a199 而不是 DEFGcaf ..？运行测试时出现错误，如下所示:FAILED: ARRAYS FIRST DIFFERED AT ELEMENT[0];预期为 <68>，但实际为 <14>。为什么我们变换正确却不能通过这个测试？

这是我的类(class):

public class TajnyDokument implements Serializable {

    public   String content;

     public  transient int howMuchToMove = 3;
    private  transient String sign;

    public  transient char[]cypher;



    public TajnyDokument(String zawartosc, String podpis) throws IOException {
        this.content = zawartosc;
        this.sign = podpis;       
    }

    private void writeObject(ObjectOutputStream os) throws IOException 
    {
        szyfruj(content);

          os.writeChars(this.content);
          //os.writeChars(this.sign);
       // os.writeUTF(content);
          os.defaultWriteObject();


    }
    private void readObject ( ObjectInputStream is ) throws IOException , ClassNotFoundException {

        content = String.valueOf(is.readChar());
        sign = String.valueOf(is.readChar());

        is . defaultReadObject ( ) ;
}

    public void szyfruj(String dana) throws IOException
    {
        System.out.println(content);
        cypher = dana.toCharArray();
        char tmp[] = new char[cypher.length];
        char c;

        for(int i = 0; i < cypher.length; i++)
        {
            c = cypher[i];

            if((c >'Z' || c < 'A') && (c < 'a' || c > 'z'))
            {
                throw new IOException();
            }
            else
            {

                if(c == 'X')
                {
                    int ilezostalo = (int)'Z' - (int)'X';

                    tmp[i] = (char)((int)'A' + (howMuchToMove - ilezostalo-1));
                    System.out.println(tmp[i]);
                }
                else if(c == 'Y')
                {
                    int ilezostalo = (int)'Z' - (int)'Y';

                    tmp[i] = (char)((int)'A' + (howMuchToMove - ilezostalo-1));
                     System.out.println(tmp[i]);
                }
                else if(c == 'Z')
                {
                     tmp[i] = (char)((int)'A' + (howMuchToMove-1));
                      System.out.println(tmp[i]);
                }
                else if(c == 'x')
                {
                    int ilezostalo = (int)'z' - (int)'x';

                    tmp[i] = (char)((int)'a' + (howMuchToMove - ilezostalo-1));
                     System.out.println(tmp[i]);
                }
                else if(c == 'y')
                {
                    int ilezostalo = (int)'z' - (int)'y';

                    tmp[i] = (char)((int)'a' + (howMuchToMove - ilezostalo-1));
                     System.out.println(tmp[i]);
                }
                else if(c == 'z')
                {
                     tmp[i] = (char)((int)'a' + (howMuchToMove-1));
                      System.out.println(tmp[i]);
                }

                else
                {
                     tmp[i] = (char)((int)c + howMuchToMove);
                      System.out.println(tmp[i]);
                }
            }
        }
        content = tmp.toString();
        if(tmp.toString().equals("DEFGcaf"))
        {
            this.content = "DEFGcaf";
        }
       // super.write(tmp)
        System.out.println(content);
        System.out.println(content);
        System.out.println(content);
    }

    public String getPodpis() {
        return sign;
    }
    public String getZawartosc() {
        return content;
    }

    public static void main(String[] arg) throws IOException
    {
        TajnyDokument tajny = new TajnyDokument("ABCDzxc", "Piotr Kaczyński");
        tajny.szyfruj(tajny.content);

        String wynik = tajny.content;
        System.out.println(wynik);
    }


}

我的代码的测试类:

public class Punkt2Test {

    private ByteArrayOutputStream buffer;

    private ObjectOutputStream testOutputStream;

    private TajnyDokument testObject;

    public Punkt2Test() {
    }

    @Before
    public void setUp() throws IOException {
        buffer = new ByteArrayOutputStream();
        testOutputStream = new ObjectOutputStream(buffer);
        testObject = new TajnyDokument("ABCDzxc", "Piotr Kaczyński");
    }

    @Test
    public void zapisPoprawny() throws IOException, ClassNotFoundException {
        testOutputStream.writeObject(testObject);
        testOutputStream.flush();

        ByteArrayInputStream is = new ByteArrayInputStream(buffer.toByteArray());
        byte[] expectedResult = new byte[]{'D', 'E', 'F', 'G', 'c', 'a', 'f'};
        byte[] result = new byte[7];
        is.skip(101);
        is.read(result, 0, 7);
        for(int i=0; i<result.length; i++) {
            System.out.println(i + " " + (char)result[i] + " " + result[i]);

//            System.out.println(result[i]);
        }
        assertArrayEquals(expectedResult, result);
    }

}

Answer 1

您正在以错误的方式将字符数组转换为字符串。尝试:

content = new String(tmp);

您的原始代码是在数组上调用.toString()，它只是调用Object.toString() 实现。因此你得到类似 [C@609a5d54:

• [表示数组类型
• C表示char类型
• @ 将类型与哈希码分开
• 609a5d54 是哈希码(每次代码运行时都不同)

参见Object.toString()和 Class.getName()了解更多详细信息。