Chương trình quản lý sinh viên bằng HashMap - Java Advanced

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 * Click nbfs://nbhost/SystemFileSystem/Templates/Classes/Class.java to edit this template
 */
package java2.lesson02;

import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

/**
 *
 * @author diepvan
 */
public class Test {
    public static void main(String[] args) {
        //Tạo một HashMap quản lý danh sách sinh viên, dùng rollNo -> String là key cho HashMap
        Map<String, Student> dataList = new HashMap<>();
        Scanner scan = new Scanner(System.in);
        int choose;
        
        do {            
            showMenu();
            choose = Integer.parseInt(scan.nextLine());
            
            switch (choose) {
                case 1:{
                    System.out.println("Nhap so sinh vien can them: ");
                    int n = Integer.parseInt(scan.nextLine());
                    for (int i = 0; i < n; i++) {
                        Student std = new Student();
                        std.input();
                        
                        dataList.put(std.getRollNo(), std);
                    }
                    break;
                }
                case 2: {
                    System.out.println("Danh sach sinh vien");
                    for (Map.Entry<String, Student> entry : dataList.entrySet()) {
                        Student std = entry.getValue();
                        std.display();
                    }
                    break;
                }
                case 3: {
                    System.out.println("Nhap msv tim kiem: ");
                    String rollNo = scan.nextLine();
                    
                    if(dataList.containsKey(rollNo)) {
                        dataList.get(rollNo).display();
                    } else {
                        System.out.println("Khong tim thay sinh vien");
                    }
                    break;
                }
                case 4:
                    System.out.println("Thoat!!!");
                    break;
                default:
                    System.out.println("Nhap sai!!!");
                    break;
            }
        } while (choose != 4);
    }
    
    static void showMenu() {
        System.out.println("1. Nhap N sinh vien");
        System.out.println("2. Hien thi");
        System.out.println("3. Tim kiem");
        System.out.println("4. Thoat");
        System.out.println("Chon: ");
    }
    
    /**
     * OOP -> Java 1
     */
    static class Student {
        String rollNo;
        String name;
        String gender;
        String email;
        String address;
        int age;

        public Student() {
        }

        public String getRollNo() {
            return rollNo;
        }

        public void setRollNo(String rollNo) {
            this.rollNo = rollNo;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getGender() {
            return gender;
        }

        public void setGender(String gender) {
            this.gender = gender;
        }

        public String getEmail() {
            return email;
        }

        public void setEmail(String email) {
            this.email = email;
        }

        public String getAddress() {
            return address;
        }

        public void setAddress(String address) {
            this.address = address;
        }

        public int getAge() {
            return age;
        }

        public void setAge(int age) {
            this.age = age;
        }
        
        public void input() {
            Scanner scan = new Scanner(System.in);
            
            System.out.println("Nhap MSV: ");
            rollNo = scan.nextLine();
            System.out.println("Nhap ten: ");
            name = scan.nextLine();
            System.out.println("Nhap gioi tinh: ");
            gender = scan.nextLine();
            System.out.println("Nhap email: ");
            email = scan.nextLine();
            System.out.println("Nhap dia chi: ");
            address = scan.nextLine();
            System.out.println("Nhap tuoi: ");
            age = Integer.parseInt(scan.nextLine());
        }

        @Override
        public String toString() {
            return "rollNo=" + rollNo + ", name=" + name + ", gender=" + gender + ", email=" + email + ", address=" + address + ", age=" + age;
        }
        
        public void display() {
            System.out.println(this);
        }
    }
}