Java教程：构建密码管理器中的编号列表选择与数据检索

1 - website1.com
2 - website2.com
Enter the number of the website you want to access:

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

public class ListNumberingFix {

    public static void main(String[] args) {
        Scanner scnr = new Scanner(System.in);
        List<String> websiteList = new ArrayList<>();
        websiteList.add("website1.com");
        websiteList.add("website2.com");
        websiteList.add("google.com");

        // 模拟外部循环，例如用户选择“再次查看列表”
        boolean continueViewing = true;
        while (continueViewing) {
            System.out.println("\n--- Available Websites ---");
            // 每次循环都使用 for 循环的 i + 1 来生成序号
            for (int i = 0; i < websiteList.size(); i++) {
                System.out.println((i + 1) + " - " + websiteList.get(i));
            }

            System.out.println("Enter 'y' to view again, 'n' to stop:");
            String choice = scnr.next();
            if (choice.equalsIgnoreCase("n")) {
                continueViewing = false;
            }
        }
        scnr.close();
    }
}

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

// 为了更好的封装性，我们定义一个 WebsiteEntry 类来存储相关信息
class WebsiteEntry {
    String website;
    String username;
    String password;

    public WebsiteEntry(String website, String username, String password) {
        this.website = website;
        this.username = username;
        this.password = password;
    }

    public String getWebsite() { return website; }
    public String getUsername() { return username; }
    public String getPassword() { return password; }
}

public class SelectionAndRetrievalFix {

    public static void main(String[] args) {
        Scanner scnr = new Scanner(System.in);
        List<WebsiteEntry> entries = new ArrayList<>();

        // 填充示例数据
        entries.add(new WebsiteEntry("website1.com", "user1_web1", "pass123"));
        entries.add(new WebsiteEntry("website2.com", "user2_web2", "securepwd"));
        entries.add(new WebsiteEntry("example.com", "admin_example", "ex@mple!@#"));

        boolean running = true;
        while (running) {
            System.out.println("\n--- Available Websites ---");
            for (int i = 0; i < entries.size(); i++) {
                System.out.println((i + 1) + " - " + entries.get(i).getWebsite());
            }

            System.out.println("Enter the number of the website you want to access (or 0 to exit):");
            int userSelection = scnr.nextInt(); // 获取用户输入

            if (userSelection == 0) {
                running = false;
                System.out.println("Exiting. Goodbye!");
                break;
            }

            // 转换为零基索引
            int selectedIndex = userSelection - 1;

            // 输入验证：检查索引是否在有效范围内
            if (selectedIndex >= 0 && selectedIndex < entries.size()) {
                WebsiteEntry selectedEntry = entries.get(selectedIndex);
                System.out.println("\n--- Details for " + selectedEntry.getWebsite() + " ---");
                System.out.println("Website: " + selectedEntry.getWebsite());
                System.out.println("Username: " + selectedEntry.getUsername());
                System.out.println("Password: " + selectedEntry.getPassword());
            } else {
                System.out.println("Invalid selection. Please enter a number from 1 to " + entries.size() + ".");
            }
        }
        scnr.close();
    }
}