LOG.info("addContent");
String content = "heading content";
OdfTextHeading instance = new OdfTextHeading(dom);
Node node;
Assert.assertNotNull(instance);
instance.addContent(content);
node = instance.getFirstChild();
Assert.assertNotNull(node);
Assert.assertEquals(Node.TEXT_NODE, node.getNodeType());
Assert.assertEquals(content, node.getTextContent());
}