以下选项中关于如下代码的说法正确的是（），
public class TestBuffered {
public static void main(String[] args) throws IOException {
BufferedReader br = new BufferedReader(new FileReader("d:/bjsxt1.txt"));
BufferedWriter bw = new BufferedWriter(new FileWriter("d:/bjsxt2.txt"));
String str = br.readLine();
while(str != null) {
bw.write(str);
bw.newLine();
str = br.readLine();
}
bw.close();
br.close();
}
}
