《Java数据结构与算法》笔记-CH4-2用栈实现字符串反转

import java.io.BufferedReader;
import java.io.InputStreamReader;

//用栈来实现一个字符串逆序算法
/**
 * 数据结构：栈
 */
class StackW{
	private int maxSize;
	private char[] stackArray;
	private int top;
	public StackW(int max){
		maxSize = max;
		stackArray = new char[maxSize];
		top = -1;
	}
	public void push(char c){
		stackArray[++top] = c;
	}
	public char pop(){
		return stackArray[top--];
	}
	public char peek(){
		return stackArray[top];
	}
	public boolean isEmpty(){
		return (top == -1);
	}
	public boolean isFull(){
		return (top == maxSize);
	}
}
/**
 * 反转类
 */
class Reverser{
	private String input;
	private StringBuilder output;
	public Reverser(String in){
		input = in;
		output = new StringBuilder();
	}
	/**
	 * 使用定义的栈来进行字符串的反转
	 * @return
	 */
	public String doReverse(){
		int stackSize = input.length();
		StackW s = new StackW(stackSize);
		for(int j= 0;j<stackSize;j++){
			char c = input.charAt(j);
			s.push(c);
		}
		while(!s.isEmpty()){
			char ch = s.pop();
			output.append(ch);
		}
		return output.toString();
	}
}
public class WordReverse {
	public static void main(String[] args) throws Exception {
		String input, output;
		while(true){
			System.out.println("Enter a string");
			System.out.flush();
			input = getString();
			if(input.equals(""))
				break;
			Reverser re = new Reverser(input);
			output = re.doReverse();
			System.out.println("reversed:"+output);
		}
	}
	/**
	 * 从键盘读字符串
	 * @return
	 * @throws Exception
	 */
	public static String getString() throws Exception{
		InputStreamReader isr = new InputStreamReader(System.in);
		BufferedReader br = new BufferedReader(isr);
		String s = br.readLine();
		return s;
	}
}