public void execute()

in src/main/org/apache/tools/ant/taskdefs/email/EmailTask.java [443:594]
126 lines of code
40 McCabe index (conditional complexity)

    public void execute() {
        Message savedMessage = message;

        try {
            Mailer mailer = null;

            // prepare for the auto select mechanism
            boolean autoFound = false;
            // try MIME format
            if (MIME.equals(encoding) || AUTO.equals(encoding)) {
                try {
                    mailer = ClasspathUtils.newInstance(getMailerImplementation(),
                            EmailTask.class.getClassLoader(), Mailer.class);
                    autoFound = true;

                    log("Using MIME mail", Project.MSG_VERBOSE);
                } catch (BuildException e) {
                    logBuildException("Failed to initialise MIME mail: ", e);
                }
            }
            // SMTP auth only allowed with MIME mail
            if (!autoFound && ((user != null) || (password != null))
                && (UU.equals(encoding) || PLAIN.equals(encoding))) {
                throw new BuildException("SMTP auth only possible with MIME mail");
            }
            // SSL only allowed with MIME mail
            if (!autoFound  && (ssl || starttls)
                && (UU.equals(encoding) || PLAIN.equals(encoding))) {
                throw new BuildException(
                    "SSL and STARTTLS only possible with MIME mail");
            }
            // try UU format
            if (UU.equals(encoding)
                 || (AUTO.equals(encoding) && !autoFound)) {
                try {
                    mailer = ClasspathUtils.newInstance(
                            "org.apache.tools.ant.taskdefs.email.UUMailer",
                            EmailTask.class.getClassLoader(), Mailer.class);
                    autoFound = true;
                    log("Using UU mail", Project.MSG_VERBOSE);
                } catch (BuildException e) {
                    logBuildException("Failed to initialise UU mail: ", e);
                }
            }
            // try plain format
            if (PLAIN.equals(encoding)
                 || (AUTO.equals(encoding) && !autoFound)) {
                mailer = new PlainMailer();
                autoFound = true;
                log("Using plain mail", Project.MSG_VERBOSE);
            }
            // a valid mailer must be present by now
            if (mailer == null) {
                throw new BuildException("Failed to initialise encoding: %s",
                    encoding);
            }
            // a valid message is required
            if (message == null) {
                message = new Message();
                message.setProject(getProject());
            }
            // an address to send from is required
            if (from == null || from.getAddress() == null) {
                throw new BuildException("A from element is required");
            }
            // at least one address to send to/cc/bcc is required
            if (toList.isEmpty() && ccList.isEmpty() && bccList.isEmpty()) {
                throw new BuildException(
                    "At least one of to, cc or bcc must be supplied");
            }
            // set the mimetype if not done already (and required)
            if (messageMimeType != null) {
                if (message.isMimeTypeSpecified()) {
                    throw new BuildException(
                        "The mime type can only be specified in one location");
                }
                message.setMimeType(messageMimeType);
            }
            // set the character set if not done already (and required)
            if (charset != null) {
                if (message.getCharset() != null) {
                    throw new BuildException(
                        "The charset can only be specified in one location");
                }
                message.setCharset(charset);
            }
            message.setInputEncoding(messageFileInputEncoding);

            // identify which files should be attached
            Vector<File> files = new Vector<>();

            if (attachments != null) {
                for (Resource r : attachments) {
                    files.add(r.as(FileProvider.class).getFile());
                }
            }
            // let the user know what's going to happen
            log("Sending email: " + subject, Project.MSG_INFO);
            log("From " + from, Project.MSG_VERBOSE);
            log("ReplyTo " + replyToList, Project.MSG_VERBOSE);
            log("To " + toList, Project.MSG_VERBOSE);
            log("Cc " + ccList, Project.MSG_VERBOSE);
            log("Bcc " + bccList, Project.MSG_VERBOSE);

            // pass the params to the mailer
            mailer.setHost(host);
            if (port != null) {
                mailer.setPort(port);
                mailer.setPortExplicitlySpecified(true);
            } else {
                mailer.setPort(SMTP_PORT);
                mailer.setPortExplicitlySpecified(false);
            }
            mailer.setUser(user);
            mailer.setPassword(password);
            mailer.setSSL(ssl);
            mailer.setEnableStartTLS(starttls);
            mailer.setMessage(message);
            mailer.setFrom(from);
            mailer.setReplyToList(replyToList);
            mailer.setToList(toList);
            mailer.setCcList(ccList);
            mailer.setBccList(bccList);
            mailer.setFiles(files);
            mailer.setSubject(subject);
            mailer.setTask(this);
            mailer.setIncludeFileNames(includeFileNames);
            mailer.setHeaders(headers);
            mailer.setIgnoreInvalidRecipients(ignoreInvalidRecipients);

            // send the email
            mailer.send();

            // let the user know what happened
            int count = files.size();

            log("Sent email with " + count + " attachment"
                 + (count == 1 ? "" : "s"), Project.MSG_INFO);
        } catch (BuildException e) {
            logBuildException("Failed to send email: ", e);
            if (failOnError) {
                throw e;
            }
        } catch (Exception e) {
          log("Failed to send email: " + e.getMessage(), Project.MSG_WARN);
          if (failOnError) {
            throw new BuildException(e);
          }
        } finally {
            message = savedMessage;
        }
    }