很久前记录过一篇创建PDF 的文章，可以参考这里 java 利用 itext 创建pdf. 一般只是创建pdf, 但有些特殊情况还需要合并pdf 与拆分pdf, 这些功能对一iText 来说，不过是小菜一碟。创建pdf 的方法还是参考以前的文章吧，毕竟里面给出的函数齐全一些。今天用iText 5.0 测试了PDF 的合并与拆分，效果还是很好的，而且性能也不错。
java itext 合并PDF
1. 首先准备要合并的pdf，将内容放在一个 InputStream list 中，准备好目标文件目录
2. 调用 合并 pdf 的方法: concatPDFs, 传入输入流list, 输出文件流，是否处理分页参数.
3. 在 concatPDFs 方法中循环处理 将输入流转换成 PdfReader，并处理页码.
4. 利用 Document class和 PdfWriter.getInstance() 方法生成目标文件
5. 在循环中将所有输入的 PDF 合并到输出文件中.
代码如下 ：package com.yihaomen.pdf;
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.Document;
import com.itextpdf.text.pdf.BaseFont;
import com.itextpdf.text.pdf.PdfContentByte;
import com.itextpdf.text.pdf.PdfImportedPage;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfWriter;
public class MergePDF {
public static void main(String[] args) {
try {
Listpdfs = new ArrayList();
for(int i=0;i<10;i++){
pdfs.add(new FileInputStream("d:\\pdf\\" + i +".pdf"));
}
OutputStream output = new FileOutputStream("d:\\pdf\\merge.pdf");
MergePDF.concatPDFs(pdfs, output, true);
} catch (Exception e) {
e.printStackTrace();
}
}
public static void concatPDFs(ListstreamOfPDFFiles,
OutputStream outputStream, boolean paginate) {
Document document = new Document();
try {
Listpdfs = streamOfPDFFiles;
Listreaders = new ArrayList();
int totalPages = 0;
IteratoriteratorPDFs = pdfs.iterator();
// Create Readers for the pdfs.
while (iteratorPDFs.hasNext()) {
InputStream pdf = iteratorPDFs.next();
PdfReader pdfReader = new PdfReader(pdf);
readers.add(pdfReader);
totalPages += pdfReader.getNumberOfPages();
}
// Create a writer for the outputstream
PdfWriter writer = PdfWriter.getInstance(document, outputStream);
document.open();
BaseFont bf = BaseFont.createFont(BaseFont.HELVETICA,
BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
PdfContentByte cb = writer.getDirectContent(); // Holds the PDF
// data
PdfImportedPage page;
int currentPageNumber = 0;
int pageOfCurrentReaderPDF = 0;
IteratoriteratorPDFReader = readers.iterator();
// Loop through the PDF files and add to the output.
while (iteratorPDFReader.hasNext()) {
PdfReader pdfReader = iteratorPDFReader.next();
// Create a new page in the target for each source page.
while (pageOfCurrentReaderPDF < pdfReader.getNumberOfPages()) {
document.newPage();
pageOfCurrentReaderPDF++;
currentPageNumber++;
page = writer.getImportedPage(pdfReader,
pageOfCurrentReaderPDF);
cb.addTemplate(page, 0, 0);
// Code for pagination.
if (paginate) {
cb.beginText();
cb.setFontAndSize(bf, 9);
cb.showTextAligned(PdfContentByte.ALIGN_CENTER, ""
+ currentPageNumber + " of " + totalPages, 520,
5, 0);
cb.endText();
}
}
pageOfCurrentReaderPDF = 0;
}
outputStream.flush();
document.close();
outputStream.close();
} catch (Exception e) {
e.printStackTrace();
} finally {
if (document.isOpen())
document.close();
try {
if (outputStream != null)
outputStream.close();
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
}
}
java itext 根据页码拆分 pdf 文档
目前简单实现根据页码拆分pdf 文档,代码如下:
package com.yihaomen.pdf;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import com.itextpdf.text.Document;
import com.itextpdf.text.pdf.PdfContentByte;
import com.itextpdf.text.pdf.PdfImportedPage;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfWriter;
public class SplitPDF {
public static void main(String[] args) {
try {
splitPDF(new FileInputStream("d:\\pdf\\merge.pdf"),
new FileOutputStream("d:\\pdf\\output1.pdf"), 1, 5);
splitPDF(new FileInputStream("d:\\pdf\\merge.pdf"),
new FileOutputStream("d:\\pdf\\output2.pdf"), 6, 10);
} catch (Exception e) {
e.printStackTrace();
}
}
public static void splitPDF(InputStream inputStream,
OutputStream outputStream, int fromPage, int toPage) {
Document document = new Document();
try {
PdfReader inputPDF = new PdfReader(inputStream);
int totalPages = inputPDF.getNumberOfPages();
// make fromPage equals to toPage if it is greater
if (fromPage > toPage) {
fromPage = toPage;
}
if (toPage > totalPages) {
toPage = totalPages;
}
// Create a writer for the outputstream
PdfWriter writer = PdfWriter.getInstance(document, outputStream);
document.open();
PdfContentByte cb = writer.getDirectContent(); // Holds the PDF data
PdfImportedPage page;
while (fromPage <= toPage) {
document.newPage();
page = writer.getImportedPage(inputPDF, fromPage);
cb.addTemplate(page, 0, 0);
fromPage++;
}
outputStream.flush();
document.close();
outputStream.close();
} catch (Exception e) {
e.printStackTrace();
} finally {
if (document.isOpen())
document.close();
try {
if (outputStream != null)
outputStream.close();
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
}
}
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