java--BufferedReader

public class test{    public static void main(String args[]) throws Exception {        //System.in 是InputStrema对象        //BufferedReader构造接受Reader对象        //InputStreamReader将字节流变为字符流                //从文件读入        File f = new File("E:\\demo\\my.txt");        BufferedReader buf = new BufferedReader(new FileReader(f));        String str = buf.readLine(); //以回车作为换行        System.out.println(str);        buf.close();        //从键盘读入        BufferedReader buf1 = new BufferedReader(new InputStreamReader(System.in));        System.out.print("请输入数据:");        String str1 = buf1.readLine(); //读取一行        System.out.println("输入的内容是:"+str1 + "长度:"+str1.length());    }}