Java邮件客户端

Java实现邮件客户端，其中使用的协议是SMTP协议以及TCP协议，有需要的兄弟姐妹可以下载。

package emailClient;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.base64;
import java.util.Scanner;

/**
 * 
 * @author sunyuhu
 * @category this is an email client.
 * @version v20180914
 */
public class Client {
	public static void main（String[] args）{
		//新建一个tcp连接，和网易的
		try {
			Socket client = new Socket（“smtp.qq.com“25）;
            BufferedReader br = new BufferedReader（new InputStreamReader（client.getInputStream（）））;
            String response = br.readLine（）;
            String username;                             //用户名
            String password;                             //密码
            String receiver;                             //接收用户名
            String subject;                              //邮件主题
            String str;
            StringBuffer content = new StringBuffer（）;
            if（response.equals（“220 smtp.qq.com Esmtp QQ Mail Server“））{
            	System.out.println（“客户端已经连接到腾讯邮件服务器！！“）;
            	
            	//输入EHLO指令
            	DataOutputStream dos = new DataOutputStream（client.getOutputStream（））;
    			dos.writeBytes（“HELO sunyuhu\r\n“）;
    			dos.flush（）;
    	        response = br.readLine（）;
    	        if（!response.equals（“250 smtp.qq.com“））{
    	        	 System.out.println（“命令错误！！！“）;
    	        }
    	        
    	        //输入认证指令，用户名和密码
    			dos.writeBytes（“AUTH LOGIN\r\n“）;
    			dos.flush（）;
    	        response = br.readLine（）;
    	        if（!response.equals（“334 VXNlcm5hbWU6“））{
   	        	 	System.out.println（“命令错误！！！“）;
   	            }else{
   	            	System.out.print（“请输入用户名：“）;
   	            	Scanner sc = new Scanner（System.in）;
   	            	username = sc.nextLine（）;
   	            	//base64.getEncoder（）.encodeToString（username.getBytes（））;
   	            	//dos.writeBytes（“MTI2Mzc1ODM4N0BxcS5jb20=\r\n“）;
   	            	dos.writeBytes（base64.getEncoder（）.encodeToString（username.getBytes（））+ “\r\n“）;
   	    			dos.flush（）;
   	    	        response = br.readLine（）;
	   	    	    if（!response.equals（“334 UGFzc3dvcmQ6“））{
	    	        	 	System.out.println（“用户名输入错误！！！“）;
	    	        }else{
	    	        	    System.out.println（“用户名输入成功！！！“）;
	    	            	System.out.print（“请输入密码：“）;
	    	            	sc = new Scanner（System.in）;
	    	            	password = sc.nextLine（）;
	    	            	dos.writeBytes（“dm54dmJ2YWJpbXZwaGpjZQ==\r\n“）;
	    	    			dos.flush（）;
	    	    	        response = br.readLine（）;
	    	    	        if（!response.equals（“235 Authentication successful“））{
	    	    	        	System.out.println（“密码输入错误！！！“）;
	    	    	        }else{
	    	    	        	System.out.println（“登录成功！！！“）;
	    	    	        	System.out.print（“请输入收件人：“）;
		    	            	sc = new Scanner（System.in）;
		    	     

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----

     文件        301  2018-09-14 22:42  ComputerNetworking\.classpath

     文件        394  2018-09-14 22:42  ComputerNetworking\.project

     文件        598  2018-09-14 22:42  ComputerNetworking\.settings\org.eclipse.jdt.core.prefs

     文件       4124  2018-09-14 22:42  ComputerNetworking\bin\emailClient\Client.class

     文件        807  2018-09-14 22:42  ComputerNetworking\bin\emailClient\Main$1.class

     文件       3878  2018-09-14 22:42  ComputerNetworking\bin\emailClient\Main$2.class

     文件       2565  2018-09-14 22:42  ComputerNetworking\bin\emailClient\Main.class

     文件       1141  2018-09-14 22:42  ComputerNetworking\bin\emailClient\WriteAndSendEmail$1.class

     文件       1087  2018-09-14 22:42  ComputerNetworking\bin\emailClient\WriteAndSendEmail$2.class

     文件       4471  2018-09-14 22:42  ComputerNetworking\bin\emailClient\WriteAndSendEmail$3.class

     文件       3622  2018-09-14 22:42  ComputerNetworking\bin\emailClient\WriteAndSendEmail.class

     文件       2423  2018-09-14 22:42  ComputerNetworking\bin\httpServer\HttpServer.class

     文件       1744  2018-09-14 22:42  ComputerNetworking\bin\udp\UDPClient.class

     文件       1518  2018-09-14 22:42  ComputerNetworking\bin\udp\UDPServer.class

     文件       4544  2018-09-14 22:42  ComputerNetworking\src\emailClient\Client.java

     文件       5763  2018-09-14 22:42  ComputerNetworking\src\emailClient\Main.java

     文件       7705  2018-09-14 22:42  ComputerNetworking\src\emailClient\WriteAndSendEmail.java

     文件       2261  2018-09-14 22:42  ComputerNetworking\src\httpServer\HttpServer.java

     文件       1083  2018-09-14 22:42  ComputerNetworking\src\udp\UDPClient.java

     文件        967  2018-09-14 22:42  ComputerNetworking\src\udp\UDPServer.java

     目录          0  2018-09-14 22:42  ComputerNetworking\bin\emailClient

     目录          0  2018-09-14 22:42  ComputerNetworking\bin\httpServer

     目录          0  2018-09-14 22:42  ComputerNetworking\bin\udp

     目录          0  2018-09-14 22:42  ComputerNetworking\src\emailClient

     目录          0  2018-09-14 22:42  ComputerNetworking\src\httpServer

     目录          0  2018-09-14 22:42  ComputerNetworking\src\udp

     目录          0  2018-09-14 22:42  ComputerNetworking\.settings

     目录          0  2018-09-14 22:42  ComputerNetworking\bin

     目录          0  2018-09-14 22:42  ComputerNetworking\src

     目录          0  2018-09-14 22:42  ComputerNetworking

............此处省略3个文件信息