// instantiate a Presentation object that represents a presentation file
Presentation pres = new Presentation("demo.pptx");
try {
    // save the presentation to PDF with default options
    pres.save("output.pdf", SaveFormat.Pdf);
} finally {
    if (pres != null) pres.dispose();
}

// instantiate Presentation
Presentation pres = new Presentation();
try {
    // get the first slide
    ISlide sld = (ISlide) pres.getSlides().get_Item(0);

    // add an AutoShape of Rectangle type
    IAutoShape ashp = sld.getShapes().addAutoShape(ShapeType.Rectangle, 150, 75, 150, 50);

    // add ITextFrame to the Rectangle
    ashp.addTextFrame("Hello World");

    // change the text color to Black (which is White by default)
    ashp.getTextFrame().getParagraphs().get_Item(0).getPortions().get_Item(0).getPortionFormat().getFillFormat()
            .setFillType(FillType.Solid);
    ashp.getTextFrame().getParagraphs().get_Item(0).getPortions().get_Item(0).getPortionFormat().getFillFormat()
            .getSolidFillColor().setColor(java.awt.Color.BLACK);

    // change the line color of the rectangle to White
    ashp.getShapeStyle().getLineColor().setColor(java.awt.Color.WHITE);

    // remove any fill formatting in the shape
    ashp.getFillFormat().setFillType(FillType.NoFill);

    // save the presentation to disk
    pres.save("output.pptx", SaveFormat.Pptx);
} finally {
    if (pres != null) pres.dispose();
}