java - 如何在使用堆栈时反转字符串中的单个单词？

Question

我是编程新手，正在参加初级编程类(class)。我试着四处寻找我的答案，我发现了可能有用的结果，但我不明白如何在使用堆栈时实现它们。我试图在不反转整个字符串的情况下反转字符串的单个单词。

例如:用户输入句子“Pies are great!”我需要输出为“seiP era !taerg”

到目前为止，我已经成功地编写了一个程序来反转整个字符串，因此使用上面示例的输出是:"!taerg era seiP"如您所见，我想反转单词本身而不用颠倒单词的顺序，但我必须使用堆栈来获取输入。

以下是我目前的情况:

public class ReversedString{

private static  ArrayStack<String> stack;

public static void main(String[] args) {
    stack = new ArrayStack<String>();
    String string = "";
    String stringReversed = "";

    @SuppressWarnings("resource")
    Scanner scanner = new Scanner(System.in);
    System.out.print("Enter the string that you want to reverse: ");
    string = scanner.nextLine();
    string.split(" ");

    for(int i=0; i<string.length(); i++){
        stack.push(string.substring(i, i+1));
    }   

    while(!stack.isEmpty()){
        stringReversed += stack.pop();
    }

    System.out.println("The reverse of the string is: " + stringReversed);

Answer 1

read character
while character is whitespace
    // do nothing to skip multiple whitespaces.
    read character

while character is not whitespace
    push character onto stack
    read character

// Just read a word, so now dump it back out.
while stack is not empty
    ch = pop stack
    print ch

显然，这需要在循环中才能执行多个单词。

读取字符的示例实现

int index = 0;
String theString = "Pies are great!"

char readCharacter()
{
    // TODO: needs error checking so you don't run off the end of the string.
    char ch = theString.charAt(index);
    index++;
    return ch;
}