Java - merge multiple doc / docx documents into one with Apache POI library

import java.util.stream.Stream;

import org.apache.poi.xwpf.usermodel.*;

import org.openxmlformats.schemas.wordprocessingml.x2006.main.*;

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public class WordUtils {

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    public static XWPFDocument mergeDocuments(Stream<XWPFDocument> documents) {

        XWPFDocument mergedDocuments = new XWPFDocument();

        CTDocument1 mergedCTDocument = mergedDocuments.getDocument();

        mergedCTDocument.unsetBody();  // to remove blank first page in merged document

        documents.forEach(srcDocument -> {

            CTDocument1 srcCTDocument= srcDocument.getDocument();

            if (srcCTDocument != null) {

                CTBody srcCTBody = srcCTDocument.getBody();

                if (srcCTBody != null) {

                    CTBody mergedCTBody = mergedCTDocument.addNewBody();

                    mergedCTBody.set(srcCTBody);

                }

            }

        });

        return mergedDocuments;

    }

}