Question

我有以下要求：

首先，我要动态创建PDF。然后我想要上传PDF文件的选项。最后，在单击打印按钮时，必须合并动态创建的文件和上载的文件。

单击打印按钮时，应该创建PDF并将其与上载的PDF结合使用。

到目前为止，这是我的代码。

package com.sumit.program;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import com.itextpdf.text.Chunk;
import com.itextpdf.text.Document;
import com.itextpdf.text.Element;
import com.itextpdf.text.Font;
import com.itextpdf.text.Image;
import com.itextpdf.text.Paragraph;
import com.itextpdf.text.Phrase;
import com.itextpdf.text.pdf.BaseFont;
import com.itextpdf.text.pdf.ColumnText;
import com.itextpdf.text.pdf.PdfContentByte;
import com.itextpdf.text.pdf.PdfCopy;
import com.itextpdf.text.pdf.PdfCopy.PageStamp;
import com.itextpdf.text.pdf.PdfImportedPage;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfSmartCopy;

public class CopyOfMergePdf {

    public static void main(String[] args) {
        try {
            List<InputStream> pdfs = new ArrayList<InputStream>();
            pdfs.add(new FileInputStream("C:\\Documents and Settings\\Sumit\\Desktop\\NewEcnProject\\Landscape.pdf"));
            pdfs.add(new FileInputStream("C:\\Documents and Settings\\Sumit\\Desktop\\client\\CoverSheet.pdf"));
            pdfs.add(new FileInputStream("C:\\Documents and Settings\\Sumit\\Desktop\\client\\ECNPRINTTEST_BP.pdf"));
            pdfs.add(new FileInputStream("C:\\Documents and Settings\\Sumit\\Desktop\\NewEcnProject\\Landscape.pdf"));
            pdfs.add(new FileInputStream("C:\\Documents and Settings\\Sumit\\Desktop\\NewEcnProject\\Document1.pdf"));
            pdfs.add(new FileInputStream("C:\\Documents and Settings\\Sumit\\Desktop\\NewEcnProject\\Landscape.pdf"));
            pdfs.add(new FileInputStream("C:\\Documents and Settings\\Sumit\\Desktop\\NewEcnProject\\Portrait.pdf"));
            OutputStream output = new FileOutputStream("C:\\Documents and Settings\\Sumit\\Desktop\\NewEcnProject\\merge1.pdf");
            CopyOfMergePdf.concatPDFs(pdfs, output, true);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static void concatPDFs(List<InputStream> streamOfPDFFiles,
            OutputStream outputStream, boolean paginate) {

        Document document = new Document();      
        try {
            List<InputStream> pdfs = streamOfPDFFiles;
            List<PdfReader> readers = new ArrayList<PdfReader>();
            int totalPages = 0;
            Iterator<InputStream> iteratorPDFs = pdfs.iterator(); 
            // Create Readers for the pdfs.
            int i=1;
            while (iteratorPDFs.hasNext()) {
                InputStream pdf = iteratorPDFs.next();
                PdfReader pdfReader = new PdfReader(pdf);
                System.out.println("Page size is "+pdfReader.getPageSize(1));
                readers.add(pdfReader);
                totalPages += pdfReader.getNumberOfPages();
                i++;
            }

            int j=0;
            System.out.println("Total pages are "+totalPages);
            // Create a writer for the outputstream
            PdfCopy copy = new PdfSmartCopy(document, outputStream);
            document.open();    

            PdfImportedPage page;
            PageStamp stamp;
            Chunk chunk;
            BaseFont baseFont = BaseFont.createFont("arial.ttf", BaseFont.CP1252,BaseFont.EMBEDDED);
            Iterator<PdfReader> iteratorPDFReader = readers.iterator();            
            // Loop through the PDF files and add to the output.
           i=0;
           PdfContentByte under;
            while (iteratorPDFReader.hasNext()) {
                PdfReader pdfReader = iteratorPDFReader.next();           
                // loop over the pages in that document                   
                page=copy.getImportedPage(pdfReader,pdfReader.getNumberOfPages());              
                i=i+1;
                stamp = copy.createPageStamp(page);
                chunk = new Chunk(String.format("Page %d",i));               
                chunk.setFont(new Font(baseFont));
                ColumnText.showTextAligned(stamp.getUnderContent(),
                        Element.ALIGN_CENTER, new Phrase(chunk),
                        document.getPageSize().getWidth()/2, 15, 0);

                if(i==2){


                }
                Image watermark_image = Image.getInstance("C:\\Documents and Settings\\Sumit\\Desktop\\ecn_in_pro.png");
                watermark_image.setAbsolutePosition(0,0);           
                under = stamp.getUnderContent();                
                under.addImage(watermark_image);
                stamp.alterContents();
                copy.addPage(page);
                copy.freeReader(pdfReader);
                pdfReader.close();               
            }

            outputStream.flush();
            document.close();
            outputStream.close();
            System.out.println("Merging of Pdfs is done.......");
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (document.isOpen())
                document.close();
            try {
                if (outputStream != null)
                    outputStream.close();
            } catch (IOException ioe) {
                ioe.printStackTrace();
            }
        }
    }
}

它仅将所有现有PDF文件复制到一个新文件中。如何将动态创建的文档添加到PdfCopy进程？

Answer 1

如果要在PdfCopy流程中插入空白页面，则应使用Rectangle和轮换（int）作为参数的addPage()方法

如果要在PdfCopy进程中插入包含内容的“即时”页面，则需要在内存中创建文档，向该页面添加内容并以相同方式处理该页面在处理从磁盘读取的文档时。

这样的事情：

ByteArrayOutputStream baos = new ByteArrayOutputStream();
Document document = new Document();
PdfWriter.getInstance(document, baos);
document.open();
document.add(new Paragraph("This page is empty on purpose"));
document.close();
PdfReader reader = new PdfReader(boas.toByteArray());

例如，如果您想要添加封面，您还可以先在内存中创建一个文档，例如列出所有正在合并的文档。

如何立即进行pdf写作和复制？

1 个答案: