1､引用Maven的pom.xml中引用配置
com.itextpdf
itextpdf
5.5.9
com.google.guava
guava
28.2-jre
2､使用URLConnection下载多个图片到本地
import java.io.ByteArrayOutputStream;import java.io.DataInputStream;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.net.MalformedURLException;import java.net.URL;import java.net.URLConnection;public class Utils {public static String getParam(String url, String name) { String params = url.substring(url.indexOf("?") + 1, url.length()); Map split = Splitter.on("&").withKeyValueSeparator("=").split(params); return split.get(name);} /** * @Description: 下载多个图片 * @param picurls 多个图片地址 path 图片下载存放目录 fileNames 多个文件名称 ,不传fileNames=null则取url中参数值，此时ParamName必须传 * @return void * @throws */ public static void downloadPicture(String[] picurls,String path,String[] fileNames,String ParamName) throws IOException { try { //多个图片下载地址 for(int i=0;i 0) { output.write(buffer, 0, length); } fileOutputStream.write(output.toByteArray()); dataInputStream.close(); fileOutputStream.close(); } } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } }}
3､使用IText合成多个图片到单个pdf
1) 使用IText将多个图片转成多个pdf文件
public static void imageToPDF(String path,String imagePath) {File file = new File(path);Document document = new Document(); try {PdfWriter.getInstance(document, new FileOutputStream(file));} catch (FileNotFoundException e1) {// TODO Auto-generated catch blocke1.printStackTrace();} catch (DocumentException e1) {// TODO Auto-generated catch blocke1.printStackTrace();} document.open(); document.newPage(); Image image = null;try {try {image = Image.getInstance(imagePath);} catch (BadElementException e) {// TODO Auto-generated catch blocke.printStackTrace();}} catch (MalformedURLException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();} image.setAbsolutePosition(0, 0); image.setBorderWidth(0); image.scaleAbsolute(PageSize.A4); try {document.add(image);} catch (DocumentException e) {// TODO Auto-generated catch blocke.printStackTrace();} document.close();}
2) 使用IText将多个pdf合成到一个pdf文件
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.lowagie.text.Document;import com.lowagie.text.pdf.BaseFont;import com.lowagie.text.pdf.PdfContentByte;import com.lowagie.text.pdf.PdfImportedPage;import com.lowagie.text.pdf.PdfReader;import com.lowagie.text.pdf.PdfWriter;public class MergePDF { public static void main(String[] args) { try { Listpdfs = new ArrayList (); pdfs.add(new FileInputStream("c:\\1.pdf")); pdfs.add(new FileInputStream("c:\\2.pdf")); OutputStream output = new FileOutputStream("c:\\merge.pdf"); MergePDF.concatPDFs(pdfs, output, true); } catch (Exception e) { e.printStackTrace(); } } public static void concatPDFs(List streamOfPDFFiles, OutputStream outputStream, boolean paginate) { Document document = new Document(); try { List pdfs = streamOfPDFFiles; List readers = new ArrayList (); int totalPages = 0; Iterator iteratorPDFs = 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; Iterator iteratorPDFReader = 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(); } } }}
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