Java 使用List集合实现图书增删改查

Book.java

/**
 * @Author ꧁ʚVVcatɞ꧂
 * @Date 2020/6/22 23:47 星期一
 * @ProjectName Book
 * @PackageName PACKAGE_NAME
 * @ClassName Book
 * @Email: 206647497@qq.com
 * @Blog: vvcat.io
 * @
 * @Version 1.0
 **/
public class Book {
    private int bookId;  // 图书编号

    private String bookName;   // 图书名称

    private double bookPrice;  // 图书价格

    public Book(int bookId, String bookName, double bookPrice) {
        this.bookId = bookId;
        this.bookName = bookName;
        this.bookPrice = bookPrice;
    }

    public Book() {
    }

    public int getBookId() {
        return bookId;
    }

    public void setBookId(int bookId) {
        this.bookId = bookId;
    }

    public String getBookName() {
        return bookName;
    }

    public void setBookName(String bookName) {
        this.bookName = bookName;
    }

    public double getBookPrice() {
        return bookPrice;
    }

    public void setBookPrice(double bookPrice) {
        this.bookPrice = bookPrice;
    }

    @Override
    public String toString() {
        return "Book{" +
                "bookId=" + bookId +
                ", bookName='" + bookName + '\'' +
                ", bookPrice=" + bookPrice +
                '}';
    }
}

TestBook.java

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

/**
 * @Author ꧁ʚVVcatɞ꧂
 * @Date 2020/6/22 23:49 星期一
 * @ProjectName Book
 * @PackageName PACKAGE_NAME
 * @ClassName TestBook
 * @
 * @Blog: vvcat.io
 * @
 * @Version 1.0
 **/
public class TestBook {

    static List<Book> book_list = new ArrayList<>();
    static Scanner scanner = new Scanner(System.in);

    static {
        book_list.add(new Book(100, "西游记", 55.5));
        book_list.add(new Book(101, "红楼梦", 60.0));
        book_list.add(new Book(102, "三国演义", 73.5));
        book_list.add(new Book(103, "水浒传", 80.0));
    }
    
    public static void main(String[] args) {

        while (true){
            System.out.println("1.查询图书");
            System.out.println("2.添加图书");
            System.out.println("3.更新图书");
            System.out.println("4.删除图书");
            System.out.println("5.退出系统");
            System.out.println("请输入操作");

            int num = scanner.nextInt();
            switch (num) {
                case 1:
                    selectBook();
                    break;
                case 2:
                    addBook();
                    break;
                case 3:
                    updateBook();
                    break;
                case 4:
                    deleteBook();
                    break;
                case 5:
                    System.out.println("系统已经退出。。。。");
                    return;
                default:
                    System.out.println("输入错误请重新输入");
                    break;
            }
        }
    }
    
    // 添加图书
    public static void addBook(){
        Book book = new Book();

        System.out.println("请输入图书编号:");
        int id = scanner.nextInt();
        book.setBookId(id);

        System.out.println("请输入图书名称:");
        String name = scanner.next();
        book.setBookName(name);

        System.out.println("请输入图书价格:");
        Double price = scanner.nextDouble();
        book.setBookPrice(price);

        book_list.add(book);
        System.out.println("添加成功！");

        prompt();
    }
    
     // 查询图书
    public static void selectBook() {
        for (Book book: book_list) {
            System.out.println(book);
        }
    }

 // 删除图书
    public static void deleteBook() {
        System.out.println("请输入需要删除的图书编号:");
        int id = scanner.nextInt();

        int count = 0;

        for (Book book: book_list) {
            if(id == book.getBookId()){
                book_list.remove(book);
                count++;
                break;
            }
        }

        if(count == 0){
            System.out.println("没有这本书...");
        }else {
            System.out.println("删除成功");
        }
    }

 // 修改图书
    public static void updateBook() {

        System.out.println("请输入要修改的图书编号:");
        int find_id = scanner.nextInt();
        int count = 0;

        for(int i = 0; i < book_list.size(); i++){

            Book book = book_list.get(i);

            if(find_id == book.getBookId()){
                System.out.println("已经找到图书 \n" + book_list.get(i));

                System.out.println("修改图书编号:");
                int id = scanner.nextInt();
                book.setBookId(id);

                System.out.println("修改图书名称:");
                String name = scanner.next();
                book.setBookName(name);

                System.out.println("修改图书价格:");
                Double price = scanner.nextDouble();
                book.setBookPrice(price);

                book_list.set(i, book);

                count++;
                break;
            }
        }

        if(count == 0){
            System.out.println("没有这本书...");
        }else {
            System.out.println("更新成功");
        }
    }
    
     // 循环添加图书
    public static void prompt(){
        System.out.println("是否继续添加");
        System.out.println("1.继续添加");
        System.out.println("2.结束添加");
        int num = scanner.nextInt();

        if(num == 1){
            addBook();
        }else if(num == 2){
            System.out.println("添加结束！");
        }else {
            System.out.println("输入错误！");
            prompt();
        }
    }

}