压栈出栈的方法实现字符串反转

import java.io.IOException;

public class StringReverserThroughStack {  private String input;

          private String output;

          public StringReverserThroughStack(String in) {     

                 input = in;

          }  

         public String doRev() {      

                    int stackSize = input.length();

                  Stack theStack = new Stack(stackSize);

                   for (int i = 0; i < input.length(); i++) {        

                         char ch = input.charAt(i);

                          theStack.push(ch);

      }      

                 output = "";

                 while (!theStack.isEmpty()) {        char ch = theStack.pop();

                 output = output + ch;

      }      

            return output;

  }  

  public static void main(String[] args) throws IOException {      

                String input = "www.w3cschool.cc";

                String output;

                StringReverserThroughStack theReverser = new StringReverserThroughStack(input);

                  output = theReverser.doRev();

                  System.out.println("反转前： " + input);

                  System.out.println("反转后： " + output);

       } 

     class Stack {      

                private int maxSize;

                  private char[] stackArray;

                  private int top;

      public Stack(int max) {      

                  maxSize = max;

                    stackArray = new char[maxSize];

                    top = -1;

      }     

       public void push(char j) {        

                 stackArray[++top] = j;

      }     

         public char pop() {       

                 return stackArray[top--];

      }     

         public char peek() {       

                 return stackArray[top];

          }      

        public boolean isEmpty() {       

                 return (top == -1);

      } 

 }

}