运行的程序如下

import java.io.*;

public class FileWriter{

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

BufferedReader br= new BufferedReader(new InputStreamReader(System.in));

BufferedWriter bw= new BufferedWriter(new FileWriter("line.txt"));

String s;

while(true){

System.out.println("请输入字符串");

System.out.flush();

s=br.readLine();

if(s.length()==0) break;

bw.write(s);

bw.close();

}

}

}

//始终提示不能找到FileWriter的构造函数。

错误提示为;

BufferedWriter bw= new BufferedWriter(new FileWriter("line.txt"));

^

1 error

找不到FileWriter的构造函数

这个错误有点莫名其妙啊

请各位高手帮忙看看问题出在哪?