如何在Java中读取Pop3服务器中的入站电子邮件

Question

我在一个pop3服务器上工作，该服务器将与一个域绑定以接收电子邮件。但问题是，该域不会包含特定的用户。我是说，如果有人给aaa@domain.com或者如果有人发信息给bbb@domain.com，这些电子邮件将通过我的pop3服务器所在的IP+端口输入，服务器将为每一封传入的电子邮件触发一个线程，在这些线程中，我想阅读这些电子邮件，你明白吗？这是线程在使用Javasocket侦听端口995传入的电子邮件消息后的工作方式：

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.SocketException;
import java.net.SocketTimeoutException;


public class ServerThread extends Thread {

private static final String INFO_USER_TIMEOUT = "User timed out";
private static final String INFO_USER_CONNECTED = "User connected";
private static final String INFO_USER_DISCONNECTED = "User 
disconnected";
private static final String SERVER_WELCOME = "+OK POP3 server ready";
private static final String ERROR_STREAM = "Unable to open or close the 
network stream.";
private static final String ERROR_SOCKET_STREAM_CLOSE = "Unable to close 
a socket or stream.";

/* Thread members */
private Socket socket;
private InputStreamReader streamReader;
private PrintWriter out;
private BufferedReader in;
private ICommandInterpreter interpreter;

/**
 * Initialises the thread with a name and sets the timeout for socket
 * 
 * @param socket
 *            the socket object for this thread
 * @param timeout
 *            the number of seconds of inactivity before closing the socket
 * @throws SocketException
 *             if a timeout cannot be established
 */
public ServerThread(Socket socket, int timeout) throws SocketException {
    super("Pop3ServerThread <" + socket.getInetAddress() + ">");
    
    /* Configure the class */
    this.socket = socket;
    interpreter = new CommandInterpreter();
    this.socket.setSoTimeout(timeout * 1000);
    
    /* Server connection message */
    System.out.println("[" + socket.getInetAddress() + "] "
            + INFO_USER_CONNECTED);
}

/**
 * Establishes input and output streams to/from the client and waits for
 * user commands over the socket. Commands are then parsed using the
 * CommandInterpreter and server responses are sent back over the network to
 * the client.
 * 
 * If the specified timeout for the socket was reached, the user will be
 * disconnected and the thread will end, closing any streams and sockets
 * used in the execution of the thread.
 */
@Override
public void run() {
    try {
        /* Initialise the network streams */
        streamReader = new InputStreamReader(socket.getInputStream());
        out = new PrintWriter(socket.getOutputStream(), true);
        in = new BufferedReader(streamReader);
        String input, output;

        /* Send a welcome message */
        out.println(SERVER_WELCOME);
        
        /* Thread-blocking while loop waits for commands from the client */
        while ((input = in.readLine()) != null) {

             HERE IS
             WHERE I WANT TO
             READ THE EMAIL MESSAGES
             INCOMING

             break;

        }
    } catch (SocketTimeoutException e) {
        interpreter.close();
        System.out.println("[" + socket.getInetAddress() + "] "
                + INFO_USER_TIMEOUT);
    } catch (IOException e) {
        System.err.println(ERROR_STREAM);
    } finally {
        try {
            /* Close any open streams */
            streamReader.close();
            in.close();
            out.close();
            socket.close();
        } catch (IOException e) {
            System.err.println(ERROR_SOCKET_STREAM_CLOSE);
        } finally {
            System.out.println("[" + socket.getInetAddress() + "] "
                    + INFO_USER_DISCONNECTED);
        }
    }
  }
}