Example:

// Create an empty document. It contains one empty paragraph.
Document doc = new Document();

// Create a new run of text.
Run run = new Run(doc, "Hello");

// Specify character formatting for the run of text.
Font f = run.getFont();
f.setName("Courier New");
f.setSize(36);
f.setHighlightColor(Color.YELLOW);

// Append the run of text to the end of the first paragraph
// in the body of the first section of the document.
doc.getFirstSection().getBody().getParagraphs().get(0).appendChild(run);

Example:

// Create an "empty" document. Note that like in Microsoft Word,
// the empty document has one section, body and one paragraph in it.
Document doc = new Document();

// This truly makes the document empty. No sections (not possible in Microsoft Word).
doc.removeAllChildren();


// Create a new section node.
// Note that the section has not yet been added to the document,
// but we have to specify the parent document.
Section section = new Section(doc);

// Append the section to the document.
doc.appendChild(section);

// Lets set some properties for the section.
section.getPageSetup().setSectionStart(SectionStart.NEW_PAGE);
section.getPageSetup().setPaperSize(PaperSize.LETTER);


// The section that we created is empty, lets populate it. The section needs at least the Body node.
Body body = new Body(doc);
section.appendChild(body);


// The body needs to have at least one paragraph.
// Note that the paragraph has not yet been added to the document,
// but we have to specify the parent document.
// The parent document is needed so the paragraph can correctly work
// with styles and other document-wide information.
Paragraph para = new Paragraph(doc);
body.appendChild(para);

// We can set some formatting for the paragraph
para.getParagraphFormat().setStyleName("Heading 1");
para.getParagraphFormat().setAlignment(ParagraphAlignment.CENTER);


// So far we have one empty pararagraph in the document.
// The document is valid and can be saved, but lets add some text before saving.
// Create a new run of text and add it to our paragraph.
Run run = new Run(doc);
run.setText("Hello World!");
run.getFont().setColor(Color.RED);
para.appendChild(run);


// As a matter of interest, you can retrieve text of the whole document and
// see that \u000c is automatically appended. \u000c is the end of section character.
Assert.assertEquals("Hello World!\u000c", doc.getText());

// Save the document.
doc.save(getMyDir() + "Section.CreateFromScratch Out.doc");