使用java实现一个用于接受邮件的代理服务器
时间: 2023-07-14 18:14:08 浏览: 48
实现一个用于接受邮件的代理服务器需要通过以下步骤:
1. 使用Java Socket编程创建一个服务器端程序,该程序监听特定的端口并接受客户端连接。
2. 通过Java Mail API实现SMTP协议,将接收到的邮件转发到指定的邮件服务器。
3. 对于每封邮件,可以使用Java Mail API将邮件内容存储到本地磁盘或数据库中。
下面是一个简单的Java代理服务器代码示例:
```java
import java.net.*;
import java.io.*;
public class MailProxyServer {
public static void main(String[] args) throws IOException {
ServerSocket serverSocket = null;
try {
serverSocket = new ServerSocket(25);
} catch (IOException e) {
System.err.println("Could not listen on port: 25.");
System.exit(1);
}
Socket clientSocket = null;
System.out.println("Waiting for connection.....");
try {
clientSocket = serverSocket.accept();
} catch (IOException e) {
System.err.println("Accept failed.");
System.exit(1);
}
System.out.println("Connection successful");
System.out.println("Waiting for input.....");
PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);
BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
String inputLine;
while ((inputLine = in.readLine()) != null) {
System.out.println("Server: " + inputLine);
if (inputLine.startsWith("MAIL FROM:")) {
// 截取发件人地址
String fromAddress = inputLine.substring(inputLine.indexOf("<") + 1, inputLine.indexOf(">"));
System.out.println("From address: " + fromAddress);
// 使用Java Mail API将邮件转发到指定的邮件服务器
sendMail(fromAddress, "to@example.com", "Subject", "Body");
}
out.println(inputLine);
if (inputLine.equals("QUIT")) {
break;
}
}
out.close();
in.close();
clientSocket.close();
serverSocket.close();
}
private static void sendMail(String fromAddress, String toAddress, String subject, String body) {
// 创建邮件会话
Session session = Session.getDefaultInstance(System.getProperties(), null);
try {
// 创建邮件消息
MimeMessage message = new MimeMessage(session);
message.setFrom(new InternetAddress(fromAddress));
message.addRecipient(Message.RecipientType.TO, new InternetAddress(toAddress));
message.setSubject(subject);
message.setText(body);
// 发送邮件
Transport.send(message);
System.out.println("Mail sent successfully.");
} catch (MessagingException e) {
e.printStackTrace();
}
}
}
```
注意:这只是一个简单的示例代码,实际应用中需要考虑更多的异常处理、安全和性能问题。