如何解决 Java BufferString 问题？我的意思是清除缓冲区

Question

我的代码没有什么问题，我将 Java 字符串拆分为 table，然后我选择了选定的字符并将其替换为 StringBuffer 方法。问题是当我在提取的 toString() 的最后使用 sout 方法时，我的加密值会自动显示为我在开始时想要加密的原始值。我尝试了很多清除 BufferedStream 但无法解除它。另见下图代码 enter image description here

public class third {
    public static void main(String[] args) {
        String letter = "drukarka";
        String[] tab1 = letter.split("");
        String result = "Result of cypher: ";
        StringBuffer cypher = new StringBuffer("drukarka");


        for (int i = 0; i < tab1.length; i++) {
            String word = tab1[i];
            int k = tab1.length;
            k--;
            if (word.equals("d")) {
                cypher.replace(Integer.valueOf(tab1.length-k-1), Integer.valueOf(tab1.length-k-1), "#");
            } else if (word.equals("r")) {
                cypher.replace(Integer.valueOf(tab1.length-k-1), Integer.valueOf(tab1.length-k-1), "!");
            } else if (word.equals("u")) {
                cypher.replace(Integer.valueOf(tab1.length-k-1), Integer.valueOf(tab1.length-k-1), "$");
            } else if (word.equals("k")) {
                cypher.replace(Integer.valueOf(tab1.length-k-1), Integer.valueOf(tab1.length-k-1), "&");
            } else if (word.equals("a")) {
                cypher.replace(Integer.valueOf(tab1.length-k-1), Integer.valueOf(tab1.length-k-1), ";");
            }
        }
        String[] cypher2 = cypher.toString().split("");
        StringBuffer cypher3 = new StringBuffer("");
        for (int i = 0; i < cypher2.length; i++) {
            cypher3.append(cypher2[i]);
        }
        String cyphered = String.valueOf(cypher3);
        cypher.setLength(0);
        cypher3.setLength(0 );
        thirdd construction = new thirdd();
        construction.constructor(letter, result, cyphered);
        System.out.println(construction.toString());
    }

}

Answer 1

你的代码有点奇怪。您想要替换 cypher 中的字母，但您并没有替换它们。相反，您似乎总是在字符串的末尾插入替换项。

我想你想要这样的东西（未测试）

public class third {
    public static void main(String[] args) {
        String input = "drukarka";
        StringBuffer cypher = new StringBuffer();

        // Get each character in the input string
        for (int i = 0; i < input.length; i++) {
            // Append a new cypher character depending on the input character
            switch (input.charAt(i))
                case 'd':
                    cypher.append('#');
                    break;
                case 'r':
                    cypher.append('!');
                    break;
                case 'u':
                    cypher.append('$');
                    break;
                case 'k':
                    cypher.append('&');
                    break;
                case 'a':
                    cypher.append(';');
                    break;
            }
        }

        String result = cypher.toString();

        // Rest of the code skipped because I'm not sure what you are trying to do.
    }

}

或者更简单的版本：

public class third {

    public static void main(String[] args) {
        String input = "drukarka";
        StringBuffer cypher = new StringBuffer();
        HashMap<Character, Character> charMap = new HashMap<>();

        // Create a map that maps an input character to its cypher version
        charMap.add('d', '#');
        charMap.add('r', '!');
        charMap.add('u', '$');
        charMap.add('k', '&');
        charMap.add('a', ';');

        for (int i = 0; i < input.length; i++) {
            // look up each character in the charMap and
            // append it to our output cypher
            cypher.append( charMap.get(input.charAt(i)) );
        }

        String result = cypher.toString();
    }

}

如何解决 Java BufferString 问题？我的意思是清除缓冲区

How to solve Java BufferString problem? I mean clearing buffer

java

oop

string

stringbuffer