数据库实训第一个项目

主类

import java.util.ArrayList;
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        // 通过Scanner可以从控制台读取用户输入的数据
        Scanner scanner = new Scanner(System.in);
        ArrayList<Student> list = new ArrayList<Student>();

        while (true) {
            // Unreachable code
            System.out.println("请输入id：");
            int id = scanner.nextInt();
            System.out.println("请输入名字:");
            String name = scanner.next();
            System.out.println("请输入年龄：");
            int age = scanner.nextInt();
            System.out.println("请输入性别:");
            String gender = scanner.next();
            Student student = new Student(id, name, age, gender);
            list.add(student);

            System.out.println("您是否要退出： -1退出, 0继续");
            int quit = scanner.nextInt();
            if (quit == -1) {
                break;
            }
        }

        for (Student student : list) {
            System.out.println(student);
        }

        while (true) {
            System.out.println("-------------------------");
            System.out.println("根据id搜索输入1");
            System.out.println("根据name搜索输入2");
            System.out.println("根据age搜索输入3");
            System.out.println("根据gender搜索输入4");
            System.out.println("您是否要退出： -1退出, 0继续");
            System.out.println("-------------------------");
            int type = scanner.nextInt();
            if (type == -1) {
                System.out.println("退出程序");
                break;
            }
            boolean search = false;//未找到该学生
            switch (type) {
            case 1:// 根据id搜索
                System.out.println("请输入要搜索的id");
                int id = scanner.nextInt();
                for (Student student : list) {
                    if (id == student.getId()) {
                        System.out.println(student);
                        search = true;
                    }
                }
                if(search == false) {
                    System.out.println("没有该id的学生");
                }
                break;
            case 2:// 根据name搜索
                System.out.println("请输入要搜索的名字：");
                String name = scanner.next();
                for (Student student : list) {
                    // 在java里面判断字符串的内容是不是相等使用equal的方法
                    if (name.equals(student.getName())) {
                        System.out.println(student);
                        search = true;
                    }
                }
                if(search == false) {
                    System.out.println("没有该名字的学生");
                }
                break;
            case 3:// 根据age搜索
                System.out.println("请输入要搜索的年龄");
                int age = scanner.nextInt();
                for (Student student : list) {
                    if (age == student.getAge()) {
                        System.out.println(student);
                        search = true;
                    }
                }
                if(search == false) {
                    System.out.println("没有该年龄的学生");
                }
                break;
            case 4:// 根据gender搜索
                System.out.println("请输入要搜索的性别：");
                String gender = scanner.next();
                for (Student student : list) {
                    // 在java里面判断字符串的内容是不是相等使用equal的方法
                    if (gender.equals(student.getGender())) {
                        System.out.println(student);
                        search = true;
                    }
                }
                if(search == false) {
                    System.out.println("没有该性别的学生");
                }
                break;

            default:
                break;
            }
        }

    }
}

类

public class Student {
    private int id;
    private String name;
    public int age;
    private String gender;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public Student(int id, String name, int age, String gender) {
        super();
        this.id = id;
        this.name = name;
        this.age = age;
        this.gender = gender;
    }

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

    public Student() {
        super();
        // TODO Auto-generated constructor stub
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getGender() {
        return gender;
    }

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

    @Override
    public String toString() {
        return "Student [id=" + id + ", name=" + name + ", age=" + age + ", gender=" + gender + "]";
    }
}