MailAdapterTest.java

private static final int NONSTANDARD_PORT = 9999;
private MailAdapter mailAdapter = new MailAdapter("localhost", NONSTANDARD_PORT);
private SimpleSmtpServer smtpServer;

@Before
public void setUp() throws Exception {
    smtpServer = SimpleSmtpServer.start(NONSTANDARD_PORT);
}

@After
public void tearDown() throws Exception {
    smtpServer.stop();
}

@Test
public void sendEmailMessage() throws Exception {
    mailAdapter.sendMessage("the subject", "the body", "foo@bar.com");

    assertEquals("message not sent?", 1, smtpServer.getReceivedEmailSize());
    SmtpMessage message = (SmtpMessage) smtpServer.getReceivedEmail().next();
    assertEquals("the body", message.getBody());
    assertEquals("the subject", message.getHeaderValue("Subject"));
    String[] recipients = message.getHeaderValues("To");
    assertEquals(1, recipients.length);
    assertEquals("foo@bar.com", recipients[0].toString());
}