This Gist will convert a Static XFA Form to an AcroForm by removing the XFA dictionary.

StaticXFA2AcroForm.java

/*
  * Copyright Datalogics, Inc. 2015
 */

package pdfjt.cookbook.forms;

import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;

import pdfjt.util.SampleFileServices;

import com.adobe.internal.io.ByteReader;
import com.adobe.internal.io.ByteWriter;
import com.adobe.internal.io.InputStreamByteReader;
import com.adobe.pdfjt.core.types.ASString;
import com.adobe.pdfjt.pdf.document.PDFDocument;
import com.adobe.pdfjt.pdf.document.PDFOpenOptions;
import com.adobe.pdfjt.pdf.document.PDFSaveFullOptions;
import com.adobe.pdfjt.pdf.interactive.forms.PDFNamedJavaScripts;
import com.adobe.pdfjt.services.xfa.XFAService;

/**
 * This sample will remove the XFA dictionary from a PDF file.
 */
public class StaticXFA2AcroForm {

    private static final String inputPDFURL = "http://dev.datalogics.com/cookbook/forms/Static_XFA_Input.pdf";
    private static final String outputDir = "cookbook/Forms/output/";

    static public void main(String[] args) throws Exception {
        URLConnection connection = new URL(inputPDFURL).openConnection();
        connection.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11");
        connection.connect();
        InputStream fis = connection.getInputStream();        
        ByteReader byteReader = new InputStreamByteReader(fis);
        PDFDocument pdfDocument = PDFDocument.newInstance(byteReader, PDFOpenOptions.newInstance());
        // Make sure we have the right kind of form.
        if (pdfDocument.getInteractiveForm().hasXFA()) {
            if (XFAService.isStaticXFANonShell(pdfDocument)) {
                // Remove the XFA Dictionary
                pdfDocument.getInteractiveForm().removeXFA();
                // Remove the Scripts automatically added by LC Designer. 
                PDFNamedJavaScripts namedJavaScripts = pdfDocument.requireCatalog().getNameDictionary().getNamedJavaScripts();
                namedJavaScripts.removeEntry(new ASString("!ADBE::0100_VersChkStrings"));
                namedJavaScripts.removeEntry(new ASString("!ADBE::0100_VersChkVars"));
                namedJavaScripts.removeEntry(new ASString("!ADBE::0200_VersChkCode_XFACheck"));
                // Save the file
                String outputFileName = "Converted_AcroForm.pdf";
                ByteWriter outputFile = SampleFileServices.getRAFByteWriter(outputDir + outputFileName);
                pdfDocument.save(outputFile, PDFSaveFullOptions.newInstance());
                System.out.println("Created: " + outputFileName);
            }
            else {
                System.out.println("Not Static XFA");
            }
        }
    }
}