Góc học tập
04/03/2019 04:21:34 PM

Đọc/ghi file đơn giản với FileReader và FileWriter

import java.io.*;

import java.util.*;

class student {

            int id;

            String name;

            float GPA;

 

            void input() throws IOException {

                        Scanner objSc = new Scanner(System.in);

                        File f = new File("D:\\test.txt");

                        FileWriter fw = new FileWriter(f);

                        try {

                                    for (int i = 0; i < 3; i++) {

                                                System.out.println("Thong tin SV " + (i + 1) + ":");

                                                System.out.print("Nhap id:");

                                                this.id = objSc.nextInt();

                                                objSc.nextLine();

                                                System.out.print("Nhap ten:");

                                                this.name = objSc.nextLine();

 

                                                System.out.print("Nhap GPA:");

                                                this.GPA = objSc.nextFloat();

                                                fw.write(id + "." + this.name + " " + this.GPA+"\n");

                                    }

                        } catch (FileNotFoundException e) {

                                    e.printStackTrace();

                        }

                        fw.close();

            }

            void output() throws IOException {

                        File f = new File("D:\\test.txt");

                        FileReader fr = new FileReader(f);

                        BufferedReader br = new BufferedReader(fr);

                        String str=null;

                        try {

                                    while((str=br.readLine())!=null)

                                                System.out.println(str);

                        }catch(FileNotFoundException e) {

                                    e.printStackTrace();

                        }

                        fr.close();

                        br.close();

            }

}

public class demoFile {

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

                        student f = new student();

                        f.input();

                        f.output();

            }

}

Trương Đình Huy