//加载ppt文档
Presentation presentation = new Presentation();
presentation.loadFromFile("data/test.pptx");
//获取第一形状的所有段落
IAutoShape shape = (IAutoShape) presentation.getSlides().get(0).getShapes().get(0);
ParagraphCollection paraCollection = shape.getTextFrame().getParagraphs();
//为第一个段落设置行距为250
ParagraphEx para = paraCollection.get(0);
para.setLineSpacing(250f);
//保存文档
presentation.saveToFile("output/result.pptx", FileFormat.PPTX_2013);