字符流读数据

按单个字符读取

即用 Reader读取出来的是char数组或者String

 try{
            //1.创建字符流输入对象
            Reader reader = new FileReader("lib/1.txt");
            //2.读取对象
//            int ch1=reader.read();
//            System.out.println(ch1);//97
//            int ch2=reader.read();
//            System.out.println(ch2);//98
//            int ch3=reader.read();
//            System.out.println(ch3);//-1
            //定义变量
            int ch;
            while ((ch=reader.read())!=-1)
            {
                System.out.println(ch);
            }
            //3.释放资源
                reader.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

多个字符读取

  Reader reader=new FileReader("lib/2.txt");//afgdgfd
//        char[] chars=new char[3];
//        int len1=reader.read(chars);
//        System.out.println(chars);//afg
//        System.out.println(len1);//3
//        int len2=reader.read(chars);
//        System.out.println(chars);//dgf
//        System.out.println(len2);//3
//        int len3=reader.read(chars);
//        System.out.println(chars);//dgf
//        System.out.println(len3);//1
        char[] chs=new char[3];
        int len;
        while ((len=reader.read(chs))!=-1)
        {
            String s=new String(chs,0,len);
            System.out.println(s);
        }
        reader.close();