--- /dev/null
+<?php
+
+namespace Drupal\rdf_test;
+
+/**
+ * Contains methods for test data conversions.
+ */
+class TestDataConverter {
+
+ /**
+ * Converts data into a string for placement into a content attribute.
+ *
+ * @param array $data
+ * The data to be altered and placed in the content attribute.
+ *
+ * @return string
+ * Returns the data.
+ */
+ public static function convertFoo($data) {
+ return 'foo' . $data['value'];
+ }
+
+}