How can I create a simple docx file with Apache POI?

Here is how you can create a simple docx file with POI :

XWPFDocument document = new XWPFDocument();
XWPFParagraph tmpParagraph = document.createParagraph();
XWPFRun tmpRun = tmpParagraph.createRun();
tmpRun.setText("LALALALAALALAAAA");
tmpRun.setFontSize(18);
document.write(new FileOutputStream(new File("yourpathhere")));
document.close();