java Socket 发送邮件

import java.io.*;
import java.net.*;
import sun.misc.*;

public class SendEmail {
PrintWriter output;
BufferedReader input;
String string;
Socket socket = null;
String user = "308727233@qq.com";

public SendEmail() {
try {
socket = new Socket("smtp.126.com", 25);
output = new PrintWriter(new OutputStreamWriter(socket
.getOutputStream()));
input = new BufferedReader(new InputStreamReader(socket
.getInputStream()));
output.println("helo 126");
output.flush();
System.out.println(input.readLine());
//验证登陆
output.println("auth login");
output.flush();
System.out.println(input.readLine());
//用户名
String username = "rainbow";
output.println(new BASE64Encoder().encode(username.getBytes()));
output.flush();
System.out.println(input.readLine());
//密码
String password = "*********";
output.println(new BASE64Encoder().encode(password.getBytes()));
output.flush();
System.out.println(input.readLine());
//发件人
output.println("mail from: ");
output.flush();
System.out.println(input.readLine());
//收件人
output.println("rcpt to: <" + this.user + ">");
output.flush();
System.out.println(input.readLine());

//内容
output.println("data");
output.flush();
System.out.println(input.readLine());
String con = "From: 网易邮箱 con += "To: <" + this.user + ">\r\n";
con = con + "Subject: 网易邮箱提醒\r\n";
con = con + "Content-Type: text/plain;charset=\"gb2312\"\r\n";
con = con + "\r\n";
con = con + "网易邮箱提醒您，有新邮件，请接收\r\n";
con = con + ".\r\n";
output.println(con);
output.flush();
System.out.println(input.readLine());
System.out.println(input.readLine());
socket.close();
input.close();
output.close();
System.out.println("Done");

} catch (Exception e) {
System.out.println("Error " + e);
return;
}

}

public static void main(String[] args) {
SendEmail client1 = new SendEmail();
}

}