Add a getter for a set of fields for flattening in PdfAcroForm

ITXT-CR-906

Author: ar3em

forms/src/main/java/com/itextpdf/forms/PdfAcroForm.java

@@ -71,6 +71,8 @@ This file is part of the iText (R) project.
 import com.itextpdf.kernel.pdf.xobject.PdfFormXObject;
 
 import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
 import java.util.List;
@@ -288,6 +290,16 @@ public Map<String, PdfFormField> getFormFields() {
         return fields;
     }
 
+    /**
+     * Gets a collection of {@link PdfFormField form field}s, prepared for flattening using {@link #partialFormFlattening} method.
+     * If returned collection is empty, all form fields will be flattened on {@link #flattenFields flattenFields} call.
+     *
+     * @return a collection of {@link PdfFormField form field}s for flattening
+     */
+    public Collection<PdfFormField> getFieldsForFlattening() {
+        return Collections.unmodifiableCollection(fieldsForFlattening);
+    }
+
     /**
      * Gets the {@link PdfDocument} this {@link PdfAcroForm} belongs to.
      *
@@ -605,7 +617,7 @@ public void setGenerateAppearance(boolean generateAppearance) {
 
     /**
      * Flattens interactive {@link PdfFormField form field}s in the document. If
-     * no fields have been explicitly included via {#link #partialFormFlattening},
+     * no fields have been explicitly included via {@link #partialFormFlattening},
      * then all fields are flattened. Otherwise only the included fields are
      * flattened.
      */

forms/src/test/java/com/itextpdf/forms/FormFieldFlatteningTest.java

@@ -73,6 +73,36 @@ public static void beforeClass() {
         createOrClearDestinationFolder(destinationFolder);
     }
 
+    @Test
+    public void getFieldsForFlatteningTest() throws IOException {
+        String outPdfName = destinationFolder + "flattenedFormField.pdf";
+        PdfDocument pdfDoc = new PdfDocument(new PdfReader(sourceFolder + "formFieldFile.pdf"), new PdfWriter(outPdfName));
+
+        PdfAcroForm form = PdfAcroForm.getAcroForm(pdfDoc, false);
+
+        Assert.assertEquals(0, form.getFieldsForFlattening().size());
+
+        form.partialFormFlattening("radioName");
+        form.partialFormFlattening("Text1");
+
+        PdfFormField radioNameField = form.getField("radioName");
+        PdfFormField text1Field = form.getField("Text1");
+
+        Assert.assertEquals(2, form.getFieldsForFlattening().size());
+        Assert.assertTrue( form.getFieldsForFlattening().contains(radioNameField));
+        Assert.assertTrue( form.getFieldsForFlattening().contains(text1Field));
+
+        form.flattenFields();
+        pdfDoc.close();
+
+        PdfDocument outPdfDoc = new PdfDocument(new PdfReader(outPdfName));
+        PdfAcroForm outPdfForm = PdfAcroForm.getAcroForm(outPdfDoc, false);
+
+        Assert.assertEquals(2, outPdfForm.getFormFields().size());
+
+        outPdfDoc.close();
+    }
+
     @Test
     public void formFlatteningTest01() throws IOException, InterruptedException {
         String srcFilename = "formFlatteningSource.pdf";