java - 如何使用 switch 语句实现字符串堆栈？

Question

我想在 switch 语句中实现我的 StringStack，我怎样才能在 java 中实现这个工作。它说我无法使用 char 值进行 push() 和参数。我的验证方法最好的解决方法是什么？

package xmlvalidator;

public class BasicXmlValidator implements XmlValidator {


    @Override
    public String[] validate(String xmlDocument) {
        // TODO Auto-generated method stub

        int charIndex = 0;
        char currentCharacter;
        String characterString;


        while (charIndex < xmlDocument.length()) {
            currentCharacter = xmlDocument.charAt(charIndex);
            characterString = Character.toString(currentCharacter);

            switch (currentCharacter) {
            case '(': StringStack.push(currentCharacter);
                break;
            case '[': StringStack.push(currentCharacter);
            break;
            case '{': StringStack.push(currentCharacter);
            break;
            case ')': StringStack.push(currentCharacter);
            break;
            case ']': StringStack.push(currentCharacter);
            break;
            case '}': StringStack.push(currentCharacter);
            break;

            }
        }


        return null;
    }

}




package xmlvalidator;

import static java.lang.System.*;

public class BasicStringStack implements StringStack {

    public int count; // Number of Items in the array

    public String[] stackItems; // The array that holds the stack items


    public BasicStringStack(int initialSize) {
        count = 0;
        stackItems = new String[initialSize];
    }


    @Override
    public void push(String item) {
        // TODO Auto-generated method stub

        if (count == stackItems.length) {
            int newLength = (stackItems.length + 1);
            String[] tempArray = new String[newLength];
            arraycopy(stackItems, 0, tempArray, 0, stackItems.length);
            stackItems = tempArray;
        }

        stackItems[count++] = item;


    }


    @Override
    public String pop() {

        if (count == 0) {
            return null;
        } else {
            return stackItems[--count];
        }


    }


    @Override
    public String peek(int position) {

        if ((position > count - 1) || (position < 0)) {
            return null; // outside Bounds
        } else {
            return stackItems[count - position - 1];
        }

    }


    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return count;
    }

}

Answer 1

您可以使用 characterString = Character.toString(currentCharacter); 将当前字符存储在字符串中，只需将其插入堆栈即可。

StringStack.push(currentCharacter);

change to

StringStack.push(currentString);