Question

I need to get an excel spreadsheet over HTTP and then send it as an attachment to an email on my Java Spring server.

The problem I am finding is that MultiPartEmail.attach() only takes a java.net.URL instance, and I cannot figure out how to ensure that the request has a certain Cookie in its headers for authentication.

url = new URL(urlString);
email.attach(url, "test.xls", "File");
email.send();

I have attempted to manually request and create a Workbook, but then I am stumped on getting the Workbook itself attached to the MultiPartEmail.

HttpClient client = new HttpClient();
GetMethod method = new GetMethod(queryString);

method.setRequestHeader("Cookie", cookie);
client.executeMethod(method);

InputStream stream = method.getResponseBodyAsStream();

Workbook workbook = Workbook.getWorkbook(stream);
email.attach(workbook, "report.xls", "forecasting report");

I need some way to work around these limitations.

Thanks in advance for your time.

Answer 1

Since you are using Spring, you can use its built-in email support to send emails. So it does not matter how you are retrieving the file from disk or somewhere else. You can send the email with attachments using MimeMessageHelper and specify the username and password for the account at the mail host for authentication like this:

public class EmailNotifier {
private JavaMailSenderImpl mailSender;

public void setMailSender(JavaMailSenderImpl mailSender) {
    this.mailSender = mailSender;
}

public void sendMail(InternetAddress fromAddress, InternetAddress toAddress, String subject, String msg) {

    MimeMessage message = mailSender.createMimeMessage();

    try {
        // use the true flag to indicate you need a multipart message
        MimeMessageHelper helper = new MimeMessageHelper(message, true);

        helper.setFrom(fromAddress);
        helper.setTo(toAddress);
        helper.setSubject(subject);
        helper.setText(msg);
        // let's attach the infamous windows Sample file (this time copied to c:/)
        FileSystemResource file = new FileSystemResource(new File("c:/test.xls"));
        helper.addAttachment("test.xls", file);
        mailSender.send(message);
    } catch (MessagingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }           
}
}

and configure a JavaMailSenderImpl bean in your bean configuration file. This is to send email via Gmail.

beans.xml

<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="mailSender" class="org.springframework.mail.javamail.JavaMailSenderImpl">
        <property name="host" value="smtp.gmail.com" />
        <property name="port" value="587" />
        <property name="username" value="adminxxxx" />
        <property name="password" value="password" />

        <property name="javaMailProperties">
           <props>
                  <prop key="mail.smtp.auth">true</prop>
                  <prop key="mail.smtp.starttls.enable">true</prop>
               </props>
        </property>
    </bean>

    <bean id="emailNotifier" class="com.examples.EmailNotifier">
        <property name="mailSender" ref="mailSender" />
    </bean>

</beans>

and this is just for testing:

public class MailApp {
  public static void main( String[] args )
    {
        ApplicationContext context = 
             new ClassPathXmlApplicationContext("beans.xml");

        EmailNotifier emailNotifier = (EmailNotifier) context.getBean("emailNotifier");
        try {
            emailNotifier.sendMail(new InternetAddress("[e-mail]"),
                    new InternetAddress("[e-mail]"),
                   "Email Alert!", 
                   "Hello User, This is a test email \n No response required.");
        } catch (AddressException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }    
    }

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