一个程序互交式逆向输出文字的JAVA算法

这是一个程序互交式的读取用户输入的多行文字，然后逆向地打印出这些文字，如果用户输入“tiuq”,程序则退出。

 

import java.io.*;

public class Test4 {
    public static void main(String args[]) throws IOException {
        char tmp;
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        for (; ; ) {
            System.out.print(">");
            String line = in.readLine();

            StringBuffer buf = new StringBuffer(line);

            for (int i = 0; i < buf.length() / 2; i++)

            {
                char c = buf.charAt(i);
                char d = buf.charAt(buf.length() - 1 - i);
                tmp = c;
                buf.setCharAt(i, d);
                buf.setCharAt(buf.length() - 1 - i, tmp);
            }
            if (buf.toString().equals("quit")) {
                break;
            }
            System.out.println(buf);

        }
    }

}