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对于家庭作业，我的任务是创建一个基于称为 Rail Fence Cipher 的方法加密字符串的程序。（我不知道这是否是常识，或者即使你们想看看它到底是什么，所以如果你也想看的话，我已经包含了维基百科的链接）。

我已经能够以直接的主要方法成功加密字符串。我现在正在使用类正确编写代码。

我不确定我是否应该只使用普通类并创建一个对象。我的第一个倾向是使类抽象，并简单地操作数据，并返回加密的方法。我不太确定这样做的正确方法是什么。我怀疑在抽象类或对象类中编写代码会有任何问题。我不确定哪个被认为是正确的。

任何人都可以提供任何指导吗？我认为不使用抽象类的最大原因是该程序很简单并且不使用任何类型的接口。

    public final class Scrambler {

private Scrambler() {

}

/*
*Scrambles a string using a three line rail fence cipher technique 
*
 */
public static String scrambleByThreeLines(String _pText) {

    //takes the message string, removes spaces, and makes lowercase
    _pText = _pText.replaceAll("[^a-zA-Z0-9]", "").toLowerCase();

    //Takes the length of the plain text string, and identifies how long it is,
    //then the next highest integer that is divisble by three
    int length = _pText.length() + (4 - (_pText.length() % 4));

    //creates a temporary array to use when populating the actual array that
    //will contain the extra null characters
    char[] tempText = _pText.toCharArray();

    //creates what will be the full array including the null characters
    char[] pText = new char[length];

    //loop to populate full array
    for (int i = 0; i < pText.length; i++) {
        if (i < tempText.length) {
            pText[i] = tempText[i];
        } else {
            pText[i] = 'x';
        }
    }
    /*Scrambling function of the cipher-------------------------------------
    *creates four strings that are concatenated togeather with a space inbetween
    *utalizing the three rail cipher technique as shown on Page 13 of the 
    *Martin Gardner book, "Codes Ciphers, and Secret Writings"
    */
    String one = "";
    String two = "";
    String three = "";
    String four = "";
    int counter = 0;
    for (int i = 0; i < pText.length; i++) {
        if ((i + 1) % 2 == 0) {
            if (counter % 2 == 0) {
                three += pText[i];
            } else {
                two += pText[i];
            }

        } else {
            if (counter % 2 == 0) {
                one += pText[i];
            } else {
                four += pText[i];
            }
            counter++;
        }
    }
    return String.format(one + " " + two + " " + three + " " + four);
}

/*
*Unscrambles a string using a three line rail fence cipher technique 
 */
public static String unscrableByThreeLines(String _cText) {
    //splits the text into the four strings to decode-----------------------
    String[] a = _cText.split(" ", 4);

    char[] one = a[0].toCharArray();
    char[] two = a[1].toCharArray();
    char[] three = a[2].toCharArray();
    char[] four = a[3].toCharArray();
    //----------------------------------------------------------------------
    //removes one char at a time in the correct order to decode to a String
    String pText = "";

    for(int i =0; i < one.length; i++){
        pText += one[i];
        pText += two[i];
        pText += four[i];
        pText += three[i];
    }

     return String.format(pText);
    }
}
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