Pigltin，难以理解如何移动“。”在一个字符串中

Question

我为我的计算机科学编写的这个程序遇到了很大的困难 class。我浏览并查看了学生在这里和其他网站上发布的其他程序，但我一直无法理解我做错了什么。我已经查看了 Java oracle 文档，它就是不合我意。

我的主要问题是应该移动“.”的嵌套部分 if 语句在单词后添加 "ay" 到句子的末尾。申请不完整。在我学会如何解决这一步之后，我将继续处理句子中第一个单词的大写。我只是不明白为什么我在使用 .substring 和 .charAt 时遇到困难。

请解释答案。

    File input = new File ("elab.txt");
    File output = new File ("elab.out");

    //create Scanner
    Scanner in = new Scanner(input);

    //create writer
    PrintWriter out = new PrintWriter(output);

    //VariParty, Part 1
    int count = 0;//Simple counter
    String word;//Scanned word from text file, will be edited
    String original;//Original word, backed up from String "word" before edit
    String original1;//Used in consonants
    String sentence = "";//Declare full sentence

    /* What I will do is scan each word in the text document. The application will display
     * a number for each word for my visual learning pleasure. The counter will be //commented
     * out as to not cause any visual action for the complete application. 
     */


    while(in.hasNext()){//Star while
        word = in.next();//Scans individual word
        word = word.toLowerCase();
        count++;//adds to counter
        original = word.toLowerCase();
        original1 = word.toLowerCase();

        //VariParty, Part 2
        char fl = word.charAt(0);
        char fL = Character.toLowerCase(word.charAt(0));
        char endChar = word.charAt(word.length()-1);


        /* This vowel portion of the application will check each "word" and deduce if "ay"
         * should be added to the end of the word beginning with a vowel. Finally, the code
         * will build onto the sentence string to produce a sentence.
         */

        if (fl == 'a' || fl == 'e' || fl == 'i'|| fl == 'o' || fl == 'u'){//Start if
        word = word + "ay";
        System.out.println(count + " VOW) " + "\"" + original + "\"" + " to " + "\"" + word + "\"" + " ");
        out.print(word + " ");                      
        sentence = sentence + " " + word;           
        }//End if


        /* We will now work towards building a better sentence. Our sentence will not have the
         * audacity to place a period in the middle of the word! Our sentences shall forever be
         * properly defined with a punctuation mark at the end, unless it's an apostrophe.              
         */

            if(word.contains(".")){//Start nested if
                word = word.substring(0,word.length()-1);
                word = word + ".";
                System.out.println(count + " NES VOW) " + "\"" + original + "\"" + " to " + "\"" + word + "\"" + " ");
            }//End nested if


        /* Now we will move the word around and deal with the consonants
         * The else statement will build the proper word by moving the first
         * letter to the end of the sentence, then adding "ay" to the end.
         * The final line will be building onto the sentence string.
         */


        else{//Start else
            word = word.substring(1,word.length());
            original = word;
            word = word + fl + "ay";
            System.out.println(count + " CON) " + "\"" + original1 + "\"" + " to " + "\"" + word + "\"" + " ");
            out.print(word + " ");

            sentence = sentence + " " + word;

        }//End else 
    }//End While

    System.out.println(sentence);
    in.close();//Close Scanner
    out.close();//Close PrintWriter

Answer 1

在下一行中，您的结束索引是词尾。因此，我不确定您在此步骤中要做什么。

word = word.substring(0,word.length()-1);

根据文档

public String substring(int beginIndex,
                    int endIndex)

所以你的步骤应该保持原样。那是你的问题吗。我无法发表评论，所以将其添加为答案...

此外，如果您在 while 循环中修改字符串，请尝试使用 Stringbuffer。

Answer 2

您应该做的第一件事是让您的程序可测试。

主要功能是将单词转换成 piglatin。因此，您应该定义一个方法来完全做到这一点：

public static String translateWordToPigLatin(String word) {
    ....
    return ...;
}

然后，您应该编写另一个名为 PigLatinTest 的 class，在其中测试此方法：

public class PigLatinTest {

    public static void main(String[] args) {
        testPigLatin("hello", "ellohay");
        testPigLatin("welcome", "ellcomeway");
        // Add more test cases here.
    }

    private static void testPigLatin(String english, String expectedPigLatin) {
        String actual = translateWordToPigLatin(english);
        if (!expectedPigLatin.equals(actual)) {
            throw new AssertionError("Expected \"" + expectedPigLatin + "\" for \"" + english + "\", got \"" + actual "\".");
        }
    }
}

在translateWordToPigLatin方法中，我调用了参数word。这是“.”的强烈指示。不属于那里。所以你真正应该做的是从一行中提取所有正确的单词，其中一个单词只包含字母。

应该调用下一个更大的方法 translateLineToPigLatin(String line)，在这个方法中，您应该：

从英文行的开头开始。
将字符复制到猪拉丁文行，直到找到一个字母。
在英文行中进一步扫描，直到找不到字母为止。
第 2 步和第 3 步之间的文本是一个单词。
将该词转换为 pig latin。
将转换后的单词添加到猪拉丁文行中。
继续浏览您离开的英文行。

Pigltin，难以理解如何移动“。”在一个字符串中

Piglatin, difficulty understanding how to move a '.' in a String

java

string

substring

charat