Sending Email through Java

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Download email JAR or define dependencies from this page
Javax mail JAR page

Create Java Web Dynamic Project

Interface

package interfaces;

import java.util.Properties;

public interface EmailI 
{
	
	public static final String USERNAME = "YOUR_EMAIL";
	public static final String PASSWORD = "YOUR_APP_PASSWORD";
	
	public static final String SMTP_GMAIL_COM = "smtp.gmail.com";
	public static final String MAIL_SMTP_PORT = "587";
	public static final String MAIL_SMTP_AUTH = "true";
	public static final String MAIL_SMTP_STARTTLS_ENABLE = "true";
   
   }

Data Access Object Level (DAO)

package DAO;

/**
 * TLS send email implimentation
 * 
 */
import java.util.Properties;

import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

import interfaces.EmailI;

public class EmailDAO implements EmailI
{	
	public  Properties getProperties()
	{
		  Properties prop = new Properties();
		    prop.put("mail.smtp.host", SMTP_GMAIL_COM);
		    prop.put("mail.smtp.port", MAIL_SMTP_PORT);
		    prop.put("mail.smtp.auth", MAIL_SMTP_AUTH);
		    prop.put("mail.smtp.starttls.enable", MAIL_SMTP_STARTTLS_ENABLE); //TLS
		    
		  return  prop;
	}
	
	
	public  Session getSession( Properties prop)
	{
		    Session session = Session.getInstance(prop,
		            new javax.mail.Authenticator() {  protected PasswordAuthentication getPasswordAuthentication()
		                 {    return new PasswordAuthentication(USERNAME, PASSWORD);       }            });		    
		  return  session;
	}
	
	
	public void sendMail(String fromEmail, String subject, String mes, Session session)
	  {
	      try {
	      	Message message = new MimeMessage(session);
	      	message.setFrom(new InternetAddress(fromEmail));  //change
	      	message.setRecipients (   Message.RecipientType.TO,   InternetAddress.parse("dzsamoila@gmail.com, admin@advicenyc.com")   );
	      	
	      message.setSubject(subject);    // change subject
	      message.setText(mes+" "+fromEmail);  // change message

	      Transport.send(message);
	      System.out.println("Done");

	  } catch (MessagingException e) 
	      { 
		 	e.printStackTrace();  
		  }	  
	}   

}

Controller level with endpoints

package controller;

import java.io.IOException;
import java.sql.SQLException;
import java.util.Date;
import java.util.Properties;

import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import DAO.EmailDAO;

/**
 * Servlet implementation class RegisterServlet1
 */
@WebServlet("/ContactServlet")
public class ContactServlet extends HttpServlet
{
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ContactServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException 
	{
		// TODO Auto-generated method stub
		response.getWriter().append("Served at: ").append(request.getContextPath());
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException 
	{
		String subject  = request.getParameter("subject");
		String email     = request.getParameter("email");		
		String message     = request.getParameter("message");

		EmailDAO emailDao = new EmailDAO();
		Properties props = emailDao.getProperties();		
		 Session session = emailDao.getSession(props);
		
		
    	  if (    (email!= null) &&(!email.isEmpty())    )
    	  {
    		 if (    (message!= null) &&(!message.isEmpty())   )
    		  {   	 System.out.println("You did it!");      			   			
    			    			  
    			try{	//Action
    				emailDao.sendMail(email, subject, message, session);	
    				}// try   
    	    	catch (Exception e)
    	    	{    	    		
    	    		request.setAttribute("errMessage", e); 
    	    		request.getRequestDispatcher("/index.jsp").forward(request, response);//forwarding the request
    	    	}
    			
    			request.setAttribute("registerOk", "You registered, please login!"); 	 			
				request.getRequestDispatcher("/ok.jsp").forward(request, response);
    			 
    		  }
    		 else //message empty
    		 {	 request.setAttribute("errMessage", "message cannot be blank"); 
    			 request.getRequestDispatcher("/register.jsp").forward(request, response);//forwarding the request
    		 }
    		  
    		  
    	  }
    	  else  //Empty email
    	  {   	 request.setAttribute("errMessage", "email cannot be blank"); 
    			 request.getRequestDispatcher("/register.jsp").forward(request, response);//forwarding the request    
    	  }
	}

	/**
	 * @see HttpServlet#doPut(HttpServletRequest, HttpServletResponse)
	 */
	protected void doPut(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {	}

}

View level PATH: /ProJECT/WebContent/index.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
				
						
					<div class="post">
						<h2 class="title-post">Contact Us </h2>
						
						  <form action="ContactServlet" method="post" onsubmit="return validate()">
						  
						<div>			
		<input type="text" name="subject" id="input-text" value="" placeholder="subject" /> <br/><br/>
		<input type="text" name="email" id="input-text" value="" placeholder="email" /> <br/><br/>
		
		<textarea name="message" id="textarea" rows="10" cols="80" placeholder="enter your message..."></textarea>
		
		<br/>
		
	
										
<button class="button register_button" id="">Submit</button>
                       </div>
                       
								</form>
						
						
						
					</div>   <!-- div post -->
					
	</body>
</html>			

Ok page /ProJECT/WebContent/ok.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>		
					<div class="post">
					<h3>You sent your Info </h3>
					</div>   <!-- div post -->
					
	</body>
</html>			

Structure of project


 

Result Email sending Form

Result if OK