Javadoc clarifications

Author: bbottema

modules/core-module/src/main/java/org/simplejavamail/api/mailer/CustomMailer.java

@@ -8,7 +8,8 @@
 
 /**
  * By default, Simple Java Mail handles the ultimate connection and sending of emails. However, it is possible to replace this last step
- * by a custom implementation.
+ * by a custom implementation. Note this is not meant to 'override' the default behavior, but to provide a custom implementation for
+ * specific use cases (for example sending using MailChimp or SendGrid, or logging to your own database).
  * <p>
  * The benefit of this is that Simple Java Mail acts as an accelarator, providing thread pool, applying email content-validation, address validations,
  * configuring a {@code Session} instance, producing a {@code MimeMessage}, all with full S/MIME, DKIM support and everything else.

modules/simple-java-mail/src/main/java/org/simplejavamail/mailer/internal/EmailGovernanceImpl.java

@@ -116,6 +116,7 @@ public EmailGovernanceImpl(@Nullable EmailValidator emailValidator, @Nullable Em
 		this.maximumEmailSize = maximumEmailSize;
 	}
 
+	// FIXME default notificationTo is missing
 	// The name is a bit cryptic, but succinct (and it's only used internally)
 	private Email newDefaultsEmailWithDefaultDefaults() {
 		final EmailPopulatingBuilder allDefaults = EmailBuilder.startingBlank();

modules/simple-java-mail/src/main/java/org/simplejavamail/mailer/internal/util/TransportRunner.java

@@ -30,6 +30,8 @@ public class TransportRunner {
 
 	/**
 	 * NOTE: only in case batch-module is *not* in use, the {@link Session} passed in here is garuanteed to be used to send this message.
+	 *
+	 * @param clusterKey The cluster key to use for the connection pool, which was randomly generated in the Mailer builder if not provided.
 	 */
 	public static void sendMessage(@NotNull final UUID clusterKey, final Session session, @NotNull Email email)
 			throws MessagingException {