Java简易邮箱模拟程序实现教程

public class Email {
    private String from;
    private String to;
    private String subject;
    private String body;
public Email(String from, String to, String subject, String body) {
    this.from = from;
    this.to = to;
    this.subject = subject;
    this.body = body;
}

// Getter方法
public String getFrom() { return from; }
public String getTo() { return to; }
public String getSubject() { return subject; }
public String getBody() { return body; }

@Override
public String toString() {
    return "From: " + from + "\nTo: " + to +
           "\nSubject: " + subject + "\nBody: " + body + "\n";
}
}

import java.util.ArrayList;
import java.util.List;
public class Mailbox {
private String owner;
private List inbox;
public Mailbox(String owner) {
    this.owner = owner;
    this.inbox = new ArrayList<>();
}

// 接收邮件
public void receiveEmail(Email email) {
    if (email.getTo().equals(owner)) {
        inbox.add(email);
        System.out.println("收件成功：来自 " + email.getFrom());
    } else {
        System.out.println("收件失败：收件人不匹配");
    }
}

// 查看所有邮件
public void viewInbox() {
    if (inbox.isEmpty()) {
        System.out.println("收件箱为空。");
    } else {
        System.out.println("\n--- 收件箱 ---");
        for (int i = 0; i < inbox.size(); i++) {
            System.out.println("邮件 " + (i+1) + ":\n" + inbox.get(i));
        }
    }
}

// 获取邮件数量
public int getEmailCount() {
    return inbox.size();
}
}

public class EmailSimulator {
    public static void main(String[] args) {
        // 创建两个邮箱用户
        Mailbox alice = new Mailbox("alice@example.com");
        Mailbox bob = new Mailbox("bob@example.com");
    // Bob 发送邮件给 Alice
    Email email1 = new Email("bob@example.com", "alice@example.com", 
                            "你好 Alice", "这是一封测试邮件！");
    alice.receiveEmail(email1);

    // 再发一封给 Bob 自己（测试错误）
    Email email2 = new Email("alice@example.com", "bob@example.com", 
                            "回复", "收到啦，谢谢！");
    alice.receiveEmail(email2); // 错误：Alice 不能接收发给 Bob 的邮件

    bob.receiveEmail(email2); // 正确接收

    // 查看邮箱
    alice.viewInbox();
    bob.viewInbox();
}
}

收件成功：来自 bob@example.com
收件失败：收件人不匹配
收件成功：来自 alice@example.com
--- 收件箱 ---
邮件 1:
From: bob@example.com
To: alice@example.com
Subject: 你好 Alice
Body: 这是一封测试邮件！
--- 收件箱 ---
邮件 1:
From: alice@example.com
To: bob@example.com
Subject: 回复
Body: 收到啦，谢谢！