Documentation – Parsing PDF documents

Java: Extract Text from PDF

Mon, 17 Feb 2025 00:00:00 +0000

Extract the Text from PDF file is a common task for Java developers. Use the Aspose.PDF for Java Pdf library to extract text in just a few lines of code. Most PDF documents are not editable, making converting the PDF to text a tedious if not impossible task, especially if the solution involves bulk processing of PDF documents. Aspose.PDF for Java library extract the text using the TextAbsorber class. Who needs text extraction?

For data mining, content management, and form processing companies, text extraction will be especially useful. Extracting text comes in handy: archiving: Text and its components can be retrieved so that documents can be indexed and archived with full search capabilities; retrieving and processing data in forms; extract information such as account data, postal addresses, and phone numbers for administrative purposes; extract photos and images.

Java: Extract Images from PDF

Mon, 17 Feb 2025 00:00:00 +0000

Each page in PDF document contain resources (images, forms and fonts). We can access to these resources by calling getResources method. Class Resources contain XImageCollection and we can get list of images by calling getImages method.

Thus to extract image from page, we need to get reference to the page, next to the page resources and last to the image collection. Particular image we can extract for example by index.

The image’s index returns an XImage object. This object provides a Save method which can be used to save the extracted image. The following code snippet shows how to extract images from a PDF file.

public static void Extract_Images(){
       // The path to the documents directory.
       String _dataDir = "/home/admin1/pdf-examples/Samples/";
       String filePath = _dataDir + "ExtractImages.pdf";

       // Load PDF document
       com.aspose.pdf.Document pdfDocument = new com.aspose.pdf.Document(filePath);

       com.aspose.pdf.Page page = pdfDocument.getPages().get_Item(1);
       com.aspose.pdf.XImageCollection xImageCollection = page.getResources().getImages();
       // Extract a particular image
       com.aspose.pdf.XImage xImage = xImageCollection.get_Item(1);

       try {
           java.io.FileOutputStream outputImage = new java.io.FileOutputStream(_dataDir + "output.jpg");
           // Save output image
           xImage.save(outputImage);
           outputImage.close();
       } catch (java.io.FileNotFoundException e) {
           // TODO: handle exception
           e.printStackTrace();
       } catch (java.io.IOException e) {
           // TODO: handle exception
           e.printStackTrace();
       }
   }

Java: Extract fonts from PDF

Mon, 17 Feb 2025 00:00:00 +0000

In case you want to get all fonts from a PDF document, you can use Document.IDocumentFontUtilities.getAllFonts() method provided in Document class. Please check following code snippet in order to get all fonts from an existing PDF document:

public static void Extract_Fonts() throws FileNotFoundException
{
    // The path to the documents directory.
    String filePath = "<... enter file name ...>";
    
    // Load PDF document
    com.aspose.pdf.Document pdfDocument = new com.aspose.pdf.Document(filePath);
    com.aspose.pdf.Font[] fonts = pdfDocument.getFontUtilities().getAllFonts();

    for (com.aspose.pdf.Font font : fonts)
    {
        font.save(new FileOutputStream(font.getFontName()));
    }
}

Java: Extract Table Data from PDF

Mon, 17 Feb 2025 00:00:00 +0000

Extract Tables from PDF programmatically

Extracting tables from PDFs is not a trivial task because the table can be created variously.

Aspose.PDF for Java has a tool to make it easy to retrieve tables. To extract table data, you should perform the following steps:

Open document - instantiate a Document object;
Create a TableAbsorber object.
Decide which pages to be analyzed and apply visit to the desired pages. The tabular data will be scanned, and the result will be saved in a list of AbsorbedTable. We can get this list through getTableList method.
To get the data iterate throught TableList and handle list of absorbed rows and list of absorbed cells. We can access to the first list by calling getTableList method and to the second by calling getCellList.
Each AbsorbedCell contains TextFragmentCollections. You can process it for your own purposes.

The following example shows table extraction from the all pages:

public static void Extract_Table() {
    // Load source PDF document        
    String filePath = "/home/aspose/pdf-examples/Samples/sample_table.pdf";
    com.aspose.pdf.Document pdfDocument = new com.aspose.pdf.Document(filePath);
    com.aspose.pdf.TableAbsorber absorber = new com.aspose.pdf.TableAbsorber();

    // Scan pages
    for (com.aspose.pdf.Page page : pdfDocument.getPages()) {
        absorber.visit(page);
        for (com.aspose.pdf.AbsorbedTable table : absorber.getTableList()) {
            System.out.println("Table");
            // Iterate throught list of rows
            for (com.aspose.pdf.AbsorbedRow row : table.getRowList()) {
                // Iterate throught list of cell
                for (com.aspose.pdf.AbsorbedCell cell : row.getCellList()) {
                    for (com.aspose.pdf.TextFragment fragment : cell.getTextFragments()) {
                        StringBuilder sb = new StringBuilder();
                        for (com.aspose.pdf.TextSegment seg : fragment.getSegments())
                            sb.append(seg.getText());
                        System.out.print(sb.toString() + "|");
                    }
                }
                System.out.println();
            }
        }
    }
}

Extract table in specific area of PDF page

Each abosorbed table has Rectangle property that describes position of the table on page.

So, if you need to extract tables located in a specific region, you have to work with specific coordinates.

The following example show how to extract table marked with Square Annotation:

public static void Extract_Marked_Table() {
    // Load source PDF document
    String filePath = "<... enter path to pdf file here ...>";
    com.aspose.pdf.Document pdfDocument = new com.aspose.pdf.Document(filePath);
    com.aspose.pdf.Page page = pdfDocument.getPages().get_Item(1);

    com.aspose.pdf.AnnotationSelector annotationSelector = new com.aspose.pdf.AnnotationSelector(
            new com.aspose.pdf.SquareAnnotation(page, com.aspose.pdf.Rectangle.getTrivial()));

    java.util.List<com.aspose.pdf.Annotation> list = annotationSelector.getSelected();
    if (list.size() == 0) {
        System.out.println("Marked tables not found..");
        return;
    }

    com.aspose.pdf.SquareAnnotation squareAnnotation = (com.aspose.pdf.SquareAnnotation) list.get(0);

    com.aspose.pdf.TableAbsorber absorber = new com.aspose.pdf.TableAbsorber();
    absorber.visit(page);

    for (com.aspose.pdf.AbsorbedTable table : absorber.getTableList()) {
        {
            boolean isInRegion = (squareAnnotation.getRect().getLLX() < table.getRectangle().getLLX())
                    && (squareAnnotation.getRect().getLLY() < table.getRectangle().getLLY())
                    && (squareAnnotation.getRect().getURX() > table.getRectangle().getURX())
                    && (squareAnnotation.getRect().getURY() > table.getRectangle().getURY());

            if (isInRegion) {
                for (com.aspose.pdf.AbsorbedRow row : table.getRowList()) {
                    {
                        for (com.aspose.pdf.AbsorbedCell cell : row.getCellList()) {
                            for (com.aspose.pdf.TextFragment fragment : cell.getTextFragments()) {
                                StringBuilder sb = new StringBuilder();
                                for (com.aspose.pdf.TextSegment seg : fragment.getSegments())
                                    sb.append(seg.getText());
                                System.out.print(sb.toString() + "|");
                            }
                        }
                        System.out.println();
                    }
                }
            }
        }
    }
}

Extract Table Data from PDF and store it in CSV file

The following example shows how to extract table and store it as CSV file. To see how to convert PDF to Excel Spreadsheet please refer to Convert PDF to Excel article.

public static void Extract_Table_Save_CSV()
{
    String filePath = "/home/admin1/pdf-examples/Samples/sample_table.pdf";
    // Load PDF document
    com.aspose.pdf.Document pdfDocument = new com.aspose.pdf.Document(filePath);

    // Instantiate ExcelSave Option object
    com.aspose.pdf.ExcelSaveOptions excelSave = new com.aspose.pdf.ExcelSaveOptions();
    excelSave.setFormat(com.aspose.pdf.ExcelSaveOptions.ExcelFormat.CSV);

    // Save the output in XLS format
    pdfDocument.save("PDFToXLS_out.xlsx", excelSave);
}

Java: Extract data from AcroForm

Mon, 17 Feb 2025 00:00:00 +0000

Extract form fields from PDF document

Aspose.PDF for Java not only lets you create and fill in form fields, but also makes it easy to extract form field data or form field information from PDF files.

Suppose we don’t know the names of the form fields in advance. Then we should iterate over each page in PDF to extract information about all AcroForms in PDF as well as the values of the form fields. To get access to the form we need to use getForm method.

public static void ExtractFormFields() {
    String path= "/home/admin/pdf-examples/Samples/StudentInfoFormElectronic.pdf";
    com.aspose.pdf.Document document = new com.aspose.pdf.Document(path);
    // Get values from all fields
    for (com.aspose.pdf.Field formField : document.getForm().getFields()) {
        System.out.println("Field Name :" + formField.getPartialName());
        System.out.println("Value : " + formField.getValue());
    }
}

If you do know the name of the form fields that you wish to extract values from then you can use indexer in Documents.Form collection to quickly retrieve this data.

Retrieve form field value by title

The form field’s Value property allows you to get the value of a particular field. To get the value, get the form field from the Document object’s form field collection. This example selects a TextBoxField and retrieves its value using the getValue method.

public static void ExtractFormDataByName() {
    String fileName = _dataDir+"/StudentInfoFormElectronic.pdf";
    com.aspose.pdf.Document document = new com.aspose.pdf.Document(fileName);        
    com.aspose.pdf.TextBoxField textBoxField1 = (com.aspose.pdf.TextBoxField)document.getForm().get("Last Name");

    System.out.println("Last Name :" + textBoxField1.getValue());
}

Extract form fields from PDF document to JSON

For export form data to JSON, we recommend using the 3rd party library like Gson. Following snippets shows how to export Name and Value to JSON:

public static void ExtractFormFieldsToJson() {
    String path = "/home/admin/pdf-examples/Samples/StudentInfoFormElectronic.pdf";
    com.aspose.pdf.Document document = new com.aspose.pdf.Document(path);

    java.util.List<FormElement> formData = new java.util.ArrayList<FormElement>();
    for (com.aspose.pdf.Field formField : document.getForm().getFields()) {
        formData.add(new FormElement(formField.getPartialName(), formField.getValue()));
    }

    Gson gson = new Gson();
    String jsonString = gson.toJson(formData);
    System.out.println(jsonString);
}

In this example we used an additional class

public class FormElement {
    public FormElement(String partialName, String Value) {
        this.Name = partialName;
        this.Value = Value;
    }
    public String Name;
    public String Value;
}

Extract Data to XML from a PDF File

Form class allows you to export data to an XML file from the PDF file using ExportXml method. In order to export data to XML, you need to create an object of Form class and then call the ExportXml method using the FileStream object. Finally, you can close FileStream object and dispose Form object. The following code snippet shows you how to export data to XML file.

public static void ExtractFormFieldsToXML() {

    String dataDir = "/home/admin/pdf-examples/Samples/StudentInfoFormElectronic.pdf";

    // Open document
    com.aspose.pdf.facades.Form form = new com.aspose.pdf.facades.Form();
    form.bindPdf(dataDir + "input.pdf");

    try {
        // Create XML file.
        FileOutputStream xmlOutputStream;

        xmlOutputStream = new FileOutputStream(dataDir + "input.xml");
        // Export data
        form.exportXml(xmlOutputStream);

        // Close file stream
        xmlOutputStream.close();

    } catch (IOException e) {

        e.printStackTrace();
    }

    // Close the document
    form.dispose();
    ;
}

Export Data to FDF from a PDF File

To export PDF forms data to XFDF file, we can use the exportFdf method in the Form class.

Please note, that it’s a class from com.aspose.pdf.facades. Despite the similar name, this class has a slightly different purpose.

In order to export data to FDF, you need to create an object of Form class and then call the exportXfdf method using the OutputStream object. The following code snippet shows you how to export data to XFDF file.

 public static void ExtractFormExportFDF() {
        String pdfFileName = Paths.get(_dataDir, "StudentInfoFormElectronic.pdf").toString();
        String fdfFileName = Paths.get(_dataDir, "student.fdf").toString();
        com.aspose.pdf.facades.Form form = new com.aspose.pdf.facades.Form(pdfFileName);

        OutputStream fdfOutputStream;
        try {

            fdfOutputStream = new FileOutputStream(fdfFileName);

            // Export data
            form.exportFdf(fdfOutputStream);

            // Close file stream
            fdfOutputStream.close();

        } catch (IOException e) {
            // TODO: handle exception
            e.printStackTrace();
        }

    }

Export Data to XFDF from a PDF File

To export PDF forms data to XFDF file, we can use the exportXfdf method in the Form class.

In order to export data to XFDF, you need to create an object of Form class and then call the exportXfdf method using the OutputStream object. The following code snippet shows you how to export data to XFDF file.

public static void ExtractFormExportXFDF() {
        String pdfFileName = Paths.get(_dataDir, "StudentInfoFormElectronic.pdf").toString();
        String fdfFileName = Paths.get(_dataDir, "student.xfdf").toString();
        com.aspose.pdf.facades.Form form = new com.aspose.pdf.facades.Form(pdfFileName);

        OutputStream fdfOutputStream;
        try {

            fdfOutputStream = new FileOutputStream(fdfFileName);

            // Export data
            form.exportXfdf(fdfOutputStream);

            // Close file stream
            fdfOutputStream.close();

        } catch (IOException e) {
            // TODO: handle exception
            e.printStackTrace();
        }
    }

Java: Extract Text From Stamps

Mon, 17 Feb 2025 00:00:00 +0000

Extract Text from Stamp Annotations

Aspose.PDF for Java lets you extract text from stamp annotations. In order to extract text from Stamp Annotations in a PDF, the following steps can be used.

Create a Document class object
Get the desired Annotation from list of annotations of a page
Define a new object of TextAbsorber class
Use the TextAbsorber’s visit method to get the Text

Document doc = new Document(dataDir+"test.pdf");
Annotation item = doc.getPages().get_Item(1).getAnnotations().get_Item(3);
if (item instanceof StampAnnotation ) {
   StampAnnotation annot = (StampAnnotation) item;
   TextAbsorber ta = new TextAbsorber();
   XForm ap = annot.getNormalAppearance();
   ta.visit(ap);
   System.out.println(ta.getText());
}