1，自定义字符数组的拷贝

        FileReader fr = new FileReader("aaa.txt");            //创建字符输入流,关联aaa.txt

        FileWriter fw = new FileWriter("bbb.txt");            //创建字符输出流,关联bbb.txt

        

        int len;

        char[] arr = new char[1024*8];                        //创建字符数组

        while((len = fr.read(arr)) != -1) {                    //将数据读到字符数组中

            fw.write(arr, 0, len);                            //从字符数组将数据写到文件上

        }

        

        fr.close();                                            //关流释放资源

        fw.close();    

2，读取文本类型

public static void demo3() throws FileNotFoundException, IOException {

        FileReader fr = new FileReader("xxx.txt");

        FileWriter fw = new FileWriter("yyy.txt");

        

        char[] arr = new char[1024];

        int len;

        while((len = fr.read(arr)) != -1) {            //将文件上的数据读取到字符数组中

            fw.write(arr,0,len);                    //将字符数组中的数据写到文件上

        }

        

        fr.close();

        fw.close();

    }