怎么用Java代码在PDF中添加注释

// Open the source PDF document
Document pdfDocument = new Document("input.pdf");
 
// Create annotation
TextAnnotation textAnnotation = new TextAnnotation(pdfDocument.getPages().get_Item(1), new com.aspose.pdf.Rectangle(200, 400, 400, 600));
 
// Set annotation title
textAnnotation.setTitle("Sample Annotation Title");
 
// Set annotation subject
textAnnotation.setSubject("Sample Subject");
textAnnotation.setState(AnnotationState.Accepted);
 
// Specify the annotation contents
textAnnotation.setContents("Sample contents for the annotation");
textAnnotation.setOpen(true);
textAnnotation.setIcon(TextIcon.Key);
Border border = new Border(textAnnotation);
border.setWidth(5);
border.setDash(new Dash(1, 1));
textAnnotation.setBorder(border);
textAnnotation.setRect(new com.aspose.pdf.Rectangle(200, 400, 400, 600));
 
// Add annotation in the annotations collection of the page
pdfDocument.getPages().get_Item(1).getAnnotations().add(textAnnotation);
 
// Save the output file
pdfDocument.save("output.pdf");