通过 Java SDK 为 PDF 文档添加下划线文字批注

    package com.aspose.asposecloudpdfusecases.annotations;

    import java.io.File;
    import java.nio.file.Path;
    import java.nio.file.StandardCopyOption;
    import java.util.ArrayList;
    import java.util.List;
    import com.aspose.asposecloudpdf.api.PdfApi;
    import com.aspose.asposecloudpdf.model.AnnotationFlags;
    import com.aspose.asposecloudpdf.model.AsposeResponse;
    import com.aspose.asposecloudpdf.model.Color;
    import com.aspose.asposecloudpdf.model.HorizontalAlignment;
    import com.aspose.asposecloudpdf.model.Point;
    import com.aspose.asposecloudpdf.model.Rectangle;
    import com.aspose.asposecloudpdf.model.UnderlineAnnotation;
    import com.aspose.asposecloudpdf.model.VerticalAlignment;

    public class AnnotationAddUnderline {
        public static void Create() {
            String REMOTE_FOLDER   = "Your_Temp_Pdf_Cloud";
            String LOCAL_FOLDER    = "c:\\Samples";
            String PDF_DOCUMENT    = "sample.pdf";
            String PDF_OUTPUT      = "annotation_add_underline_output.pdf";
            Integer PAGE_NUMBER = 1;

            String NEW_UL_ANNOTATION_TEXT        = "NEW UNDERLINE TEXT ANNOTATION";
            String NEW_UL_ANNOTATION_DESCRIPTION = "This is a sample underline text annotation";
            String NEW_UL_ANNOTATION_SUBJECT     = "Underline Text Box Subject";
            String NEW_UL_ANNOTATION_CONTENTS    = "Underline annotation sample contents";

            try {
                PdfApi pdfApi = new PdfApi(API_KEY, API_SECRET);

                // upload local PDF file to remote storage
                File file = new File(Path.of(LOCAL_FOLDER, PDF_DOCUMENT).toString());
                pdfApi.uploadFile(Path.of(REMOTE_FOLDER , PDF_DOCUMENT).toString(), file, null);
                System.out.println(String.format("File '%s' successfully uploaded!", Path.of(LOCAL_FOLDER, PDF_DOCUMENT).toString()));

                UnderlineAnnotation annotation = new UnderlineAnnotation();
                annotation.setName("Underline_Text_Annotation");
                annotation.setRect(new Rectangle().LLX(100.).LLY(350.).URX(450.).URY(400.));
                annotation.setHorizontalAlignment(HorizontalAlignment.LEFT);
                annotation.setVerticalAlignment(VerticalAlignment.TOP);
                annotation.setRichText(NEW_UL_ANNOTATION_TEXT);
                annotation.setSubject(NEW_UL_ANNOTATION_SUBJECT);
                annotation.setContents(NEW_UL_ANNOTATION_CONTENTS);
                annotation.setTitle(NEW_UL_ANNOTATION_DESCRIPTION);
                annotation.setZindex(1);
                annotation.setColor(new Color().A(255).G(255));

                annotation.setModified("11/20/2025 00:00:00.000 AM");

                List<Point> points = new ArrayList<>();
                points.add(new Point().X(10.).Y(10.));
                points.add(new Point().X(20.).Y(10.));
                points.add(new Point().X(10.).Y(20.));
                points.add(new Point().X(10.).Y(10.));

                annotation.setQuadPoints(points);

                List<AnnotationFlags> flags = new ArrayList<>();
                flags.add(AnnotationFlags.DEFAULT);
                annotation.flags(flags);

                List<UnderlineAnnotation> annotations = new ArrayList<>();
                annotations.add(annotation);

                AsposeResponse response = pdfApi.postPageUnderlineAnnotations(PDF_DOCUMENT, PAGE_NUMBER, annotations, null, REMOTE_FOLDER);
                if (response.getCode() != 200)
                    System.err.println("Error: unexpected error when adding annotation! '" + response.getStatus() + "'");
                else{
                    // download changed PDF file from remote folder...
                    File f = pdfApi.downloadFile(Path.of(REMOTE_FOLDER , PDF_DOCUMENT).toString(), null, null);
                    java.nio.file.Files.copy(Path.of(f.getPath()), Path.of(LOCAL_FOLDER, PDF_OUTPUT), StandardCopyOption.REPLACE_EXISTING);
                    System.out.println(String.format("File '%s' successfully dowloaded!", Path.of(LOCAL_FOLDER, PDF_OUTPUT).toString()));                
                    System.out.println("Successfully added annotation in document ! '" + PDF_OUTPUT + "'");
                }
            }
            catch (Exception e) {
                e.printStackTrace();
            }
        }
    }