Load specific posttype in RRS

Hey Everyone,

I have probably a simple question. I am writing a plugin that loads an RRS template for a specific costum_type. But I cannot figure out how I get the type. It’s returning all blog posts.

class RrsTemplate
{

    public function jobOfferTemplate()
    {

        header('Content-Type: ' . feed_content_type('rss-http') . '; charset=' . get_option('blog_charset'), true);
        echo '<?xml version="1.0" encoding="' . get_option('blog_charset') . '"?' . '>';
        ?>
        <rss version="2.0"
             xmlns:content="http://purl.org/rss/1.0/modules/content/"
             xmlns:wfw="http://wellformedweb.org/CommentAPI/"
             xmlns:dc="http://purl.org/dc/elements/1.1/"
             xmlns:atom="http://www.w3.org/2005/Atom"
             xmlns:sy="http://purl.org/rss/1.0/modules/syndication/"
             xmlns:slash="http://purl.org/rss/1.0/modules/slash/"
            <?php do_action('rss2_ns'); ?>>
            <channel>
                <title><?php bloginfo_rss('name'); ?> - Feed</title>
                <atom:link href="<?php self_link(); ?>" rel="self" type="application/rss+xml"/>
                <link><?php bloginfo_rss('url') ?></link>
                <description><?php bloginfo_rss('description') ?></description>
                <lastBuildDate><?php echo mysql2date('D, d M Y H:i:s +0000', get_lastpostmodified('GMT'),
                        false); ?></lastBuildDate>
                <language><?php echo get_option('rss_language'); ?></language>
                <sy:updatePeriod><?php echo apply_filters('rss_update_period', 'hourly'); ?></sy:updatePeriod>
                <sy:updateFrequency><?php echo apply_filters('rss_update_frequency', '1'); ?></sy:updateFrequency>
                <?php do_action('rss2_head'); ?>
                <?php while (have_posts()) : the_post(); ?>
                    <item>
                        <title><?php the_title_rss(); ?></title>
                        <link><?php the_permalink_rss(); ?></link>
                        <pubDate><?php echo mysql2date('D, d M Y H:i:s +0000', get_post_time('Y-m-d H:i:s', true),
                                false); ?></pubDate>
                        <dc:creator><?php the_author(); ?></dc:creator>
                        <guid isPermaLink="false"><?php the_guid(); ?></guid>
                        <description><![CDATA[<?php the_excerpt_rss() ?>]]></description>
                        <content:encoded><![CDATA[<?php the_excerpt_rss() ?>]]></content:encoded>
                        <?php rss_enclosure(); ?>
                        <?php do_action('rss2_item'); ?>
                    </item>
                <?php endwhile; ?>
            </channel>
        </rss>
        <?php

    }

    public function articles()
    {

    }