XWPFDocument doc = XWPFTestDataSamples.openSampleDocument("heading123.docx");
XWPFParagraph p = doc.createParagraph();
XWPFRun run = p.createRun();
run.setText("Heading 1");
CTSdtBlock block = doc.getDocument().getBody().addNewSdt();
assertNull(p.getStyle());
p.setStyle(HEADING1);
assertEquals(HEADING1, p.getCTP().getPPr().getPStyle().getVal());