我正在为计算机科学课写这个课程遇到很大困难。我已经看过学生们在这里和其他网站发布过的其他节目,但是我还没能理解我做错了什么。我查看了Java oracle doc,它只是没有点击我。
我的主要问题是嵌套的if语句应该移动'。'在将“ay”添加到单词后的句子结尾处。申请表尚未完成。在我可以学习如何解决这一步之后,我将继续对句子中第一个单词进行大写。我只是不明白我为什么遇到.substring和.charAt。
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
答案 0 :(得分:2)
你要做的第一件事就是让你的程序可以测试。
主要功能是将单词转换为piglatin。因此,您应该定义一个完全相同的方法:
public static String translateWordToPigLatin(String word) {
....
return ...;
}
然后,您应该编写另一个名为PigLatinTest
的类,您可以在其中测试此方法:
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
。这是一个'。'的强烈迹象。不属于那里。所以你真正要做的就是从行中提取所有正确的单词,其中一个单词只包含字母。
下一个更大的方法应该被称为translateLineToPigLatin(String line)
,在这个方法中,您应该:
答案 1 :(得分:0)
在下面一行中,您的结束索引是单词结尾。所以,我不确定你在这一步中想要做什么。
word = word.substring(0,word.length()-1);
根据文件
public String substring(int beginIndex,
int endIndex)
所以你的步骤应该保持一致。这是你的问题吗?我无法发表评论,所以将其添加为答案......
另外,如果要在while循环中修改字符串,请尝试使用Stringbuffer。