Class FormBarCode

  • All Implemented Interfaces:

    public final class FormBarCode
    extends FormElement

    A type of form element representing a BarCode. Barcode fields were added to Acrobat 7 as part of the XFA standard, and although they only became an official part of PDF as of PDF 2.0 (ISO-32000-2) they should be usable in Acrobat 7 or later (although they may not be usable in other PDF viewers).

    Barcode fields are typically used to represent the contents of other fields in the form, the idea being that if the form is printed rather than electronically submitted, the BarCode can be scanned to retrieve the form contents. The way to do this is by adding an Event.OTHERCHANGE action to the field to recalculate its value based on the other fields (although there should be other ways to do this, they're unlikely to work in Acrobat so this is the only recommended approach).

    Here's a very simple example:

     // create main form elements and add to form
     form.put("Name", namefield);
     form.put("Address", addressfield);
     String js = "var fields = [ 'Name', 'Address' ]; \
                  var val = ''; \
                  for (var f=0;f<fields.length;f++) { \
                    val = this.getField(fields[i]).value + '\t'; \
                  } \
                  event.value = val;";
     FormBarCode barcode = new FormBarCode();
     barcode.addAnnotation(page, 100, 100, 150, 150);
     barcode.setAction(Event.OTHERCHANGE, PDFAction.formJavaScript(js));
     form.put("BarCode", barcode);
    • Field Detail


        public static final int COMPRESSION_NONE
        Barcode is encoded with a value that is not compressed.
        See Also:
        Constant Field Values

        public static final int COMPRESSION_ADOBE
        Barcode is Flate-compressed, with Adobe's "special sauce" - a two byte prefix of unknown purpose. Use this for BarCodes that will be updated by Acrobat.
        See Also:
        Constant Field Values

        public static final int COMPRESSION_FLATE
        Barcode is Flate-compressed, without any prefix. Not compatible with Acrobat, but useful for documents edited only with our PDF Viewer.
        See Also:
        Constant Field Values
    • Constructor Detail

      • FormBarCode

        public FormBarCode()
        Create a new BarCode field
      • FormBarCode

        public FormBarCode​(PDFPage page,
                           float x1,
                           float y1,
                           float x2,
                           float y2)
        Create a new BarCode field and add an annotation for it to the page
        page - the page for the widget
        x1 - the left-most X co-ordinate of the annotation
        y1 - the bottom-most Y co-ordinate of the annotation
        x2 - the right-most X co-ordinate of the annotation
        y2 - the top-most Y co-ordinate of the annotation
    • Method Detail

      • addAnnotation

        public WidgetAnnotation addAnnotation​(PDFPage page,
                                              float x1,
                                              float y1,
                                              float x2,
                                              float y2)
        Create and add a new widget annotation for this field.
        page - the page for the widget
        x1 - the left-most X co-ordinate of the annotation
        y1 - the bottom-most Y co-ordinate of the annotation
        x2 - the right-most X co-ordinate of the annotation
        y2 - the top-most Y co-ordinate of the annotation
      • setValue

        public void setValue​(String value)
        Sets the value of this field
        value - the new value
      • setCompression

        public void setCompression​(int compression)
        Set whether the BarCode value should be compressed by Flate compreesion first. This is slightly non-standard and unlikely to work with many BarCode readers.
        See Also:
      • setSymbology

        public void setSymbology​(String symbology)
        Sets the type of BarCode symbology
        symbology - one of PDF417, QRCode, or DataMatrix
      • setSymbolSize

        public void setSymbolSize​(float mm)
        Set the symbol size in mm - this is the size of the smallest unit in the BarCode, and is typically in the region of 0.5 to 1. Note that we expect the value in mm, which is the units we use in the BarCode class, whereas Acrobat's UI asks for the units in points: for conversion, 2.8mm = 1pt.
        mm - the size of the smallest unit in the BarCode, in mm
        See Also:
      • setECC

        public void setECC​(int ecc)
        Sets the error correction coefficient (PDF417 and QRCode only). For PDF417 the value shall be from 0 to 8. For QRCode it shall be from 0 to 3 (0 for 'L', 1 for 'M', 2 for 'Q', and 3 for 'H').
        ecc - the error correction coefficient
      • getECC

        public int getECC()
        Return the error correction level, as set by setECC(int)
      • getCompression

        public int getCompression()
        Returns the type of compression the field is stored with, as specified by setCompression(int)
      • rebuild

        public void rebuild()
        Description copied from class: FormElement
        Cause the annotation list to be rebuilt. Unless you're rendering the annotation using the viewer, it's not necessary to call this method.
        rebuild in class FormElement
      • getTabDelimiteredJavaScript

        public static String getTabDelimiteredJavaScript​(Collection<String> names,
                                                         boolean includenames)
        Return the JavaScript used by Acrobat to set a BarCode to a tab-delimetered list of field names. For example, to include the fields "name" and "address" in the barcode, you could use the following:
         FormBarCode barcode = new FormBarCode();
         String js = FormBarCode.getTabDelimiteredJavaScript(Arrays.asList(new String[] {"Name, "Address"}), false);
         barcode.setAction(Event.OTHERCHANGE, PDFAction.formJavaScript(code));
         pdf.setJavaScript(pdf.getJavaScript() + FormBarCode.getTabDelimiteredJavaScriptSetup());
        Note that although this is the approach used by Acrobat, the generated JavaScript is a mess and you could probably do better yourself - there's no reason to rely on this JavaScript, and it's here for convenience only.
        names - the list of field names to include in the barcode value, or null for all fields
        includenames - whether to include the list of field names in the value
        See Also:
      • toString

        public String toString()
      • putLiteral

        public void putLiteral​(String key,
                               String tokens)
        Put a literal token sequnce. For debugging
        key - the key
        tokens - the token sequence, eg "true" or "/foo" or "[/Foo/Bar]". No refs, just direct objects.