Properties prop =new Properties();
        prop.put("mail.smtp.auth","true");
        prop.put("mail.smtp.starttls.enable","true");
        prop.put("mail.smtp.host","smtp.gmail.com");
        prop.put("mail.smtp.port","587");
        prop.put("mail.smtp.ssl.trust", "*");

        final String username = "andrzej.kokosza13";
        final String password = "asd1fgh2jkl3";
        final String fromEmail= "andrzej.kokosza13@gmail.com";
        final String toEmail = "katdon@st.amu.edu.pl";
        final String subject = "Spam";
        final String text = "";
        Session session = Session.getDefaultInstance(prop, new Authenticator(){
            @Override
            protected PasswordAuthentication getPasswordAuthentication(){
                return new PasswordAuthentication(username,password);
            }
        });
        for(int i=1; i<=10;i++) {
            try {
                Message message = new MimeMessage(session);
                message.setFrom(new InternetAddress(fromEmail));
                message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(toEmail));
                message.setSubject(subject);
                message.setText(text);
                Transport.send(message);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }