--添加依赖
<!-- https://mvnrepository.com/artifact/org.apache.pdfbox/pdfbox --><dependency> <groupId>org.apache.pdfbox</groupId> <artifactId>pdfbox</artifactId> <version>2.0.12</version></dependency>
--最佳实践
package com.dhht.wechat.util;import org.apache.commons.io.FileUtils;import org.apache.pdfbox.pdmodel.PDDocument;import org.apache.pdfbox.pdmodel.PDPageTree;import org.apache.pdfbox.rendering.PDFRenderer;import sun.misc.BASE64Decoder;import sun.misc.BASE64Encoder;import javax.imageio.ImageIO;import javax.servlet.ServletOutputStream;import javax.servlet.http.HttpServletResponse;import java.awt.image.BufferedImage;import java.io.*;/** * @Author: sh * @Description: PDFUtil * @Date: 11:35 2019/7/1 */public class PDFUtil { /** * 将base64字符串转换为PDF在显示到页面中 * @param base64String * @param httpServletResponse */ public static void base64StringToPDFToPage(String base64String, HttpServletResponse httpServletResponse){ BASE64Decoder decoder = new BASE64Decoder(); ByteArrayOutputStream baos = null; ServletOutputStream sos = null; try { byte[] bytes = decoder.decodeBuffer(base64String); baos = new ByteArrayOutputStream(); baos.write(bytes); //把byte写进输出流里 if (baos != null) { httpServletResponse.setContentType("application/pdf"); httpServletResponse.setContentLength(baos.size()); httpServletResponse.setHeader("Expires", "0"); httpServletResponse.setHeader("Cache-Control", "must-revalidate, post-check=0, pre-check=0"); httpServletResponse.setHeader("Pragma", "public"); // 设置打印PDF的文件名 String fileName = "社保证明文件.pdf"; fileName = new String(fileName.getBytes("UTF-8"), "ISO-8859-1"); httpServletResponse.setHeader("Content-Disposition", "filename=" + fileName); sos = httpServletResponse.getOutputStream(); baos.writeTo(sos); //byte输出流写入servlet输出流 sos.flush(); } } catch (IOException e) { e.printStackTrace(); } finally { try { sos.close(); baos.close(); } catch (IOException e) { e.printStackTrace(); } } } /** * 将base64编码转换成PDF * @param base64String * 1.使用BASE64Decoder对编码的字符串解码成字节数组 * 2.使用底层输入流ByteArrayInputStream对象从字节数组中获取数据； * 3.建立从底层输入流中读取数据的BufferedInputStream缓冲输出流对象； * 4.使用BufferedOutputStream和FileOutputSteam输出数据到指定的文件中 */ public static void base64StringToPDF(String base64String, String pdfPath/*File file*/){ File file = new File(pdfPath);// 将原来参数修改为字符串 BASE64Decoder decoder = new BASE64Decoder(); BufferedInputStream bin = null; FileOutputStream fout = null; BufferedOutputStream bout = null; try { //将base64编码的字符串解码成字节数组 byte[] bytes = decoder.decodeBuffer(base64String); //创建一个将bytes作为其缓冲区的ByteArrayInputStream对象 ByteArrayInputStream bais = new ByteArrayInputStream(bytes); //创建从底层输入流中读取数据的缓冲输入流对象 bin = new BufferedInputStream(bais); //创建到指定文件的输出流 fout = new FileOutputStream(file); //为文件输出流对接缓冲输出流对象 bout = new BufferedOutputStream(fout); byte[] buffers = new byte[1024]; int len = bin.read(buffers); while(len != -1){ bout.write(buffers, 0, len); len = bin.read(buffers); } //刷新此输出流并强制写出所有缓冲的输出字节，必须这行代码，否则有可能有问题 bout.flush(); } catch (IOException e) { e.printStackTrace(); } finally { try { bout.close(); fout.close(); bin.close(); } catch (IOException e) { e.printStackTrace(); } } } /** * PDF转换为Base64编码 * @param file * @return */ public static String pdfToBase64(File file) { BASE64Encoder encoder = new BASE64Encoder(); FileInputStream fin =null; BufferedInputStream bin =null; ByteArrayOutputStream baos = null; BufferedOutputStream bout =null; try { fin = new FileInputStream(file); bin = new BufferedInputStream(fin); baos = new ByteArrayOutputStream(); bout = new BufferedOutputStream(baos); byte[] buffer = new byte[1024]; int len = bin.read(buffer); while(len != -1){ bout.write(buffer, 0, len); len = bin.read(buffer); } //刷新此输出流并强制写出所有缓冲的输出字节 bout.flush(); byte[] bytes = baos.toByteArray(); return encoder.encodeBuffer(bytes).trim(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { try { fin.close(); bin.close(); baos.close(); bout.close(); } catch (IOException e) { e.printStackTrace(); } } return null; } /** * pdf转jpg * @param pdfPath * @param jpgPath */ public static void pdfToJpg(String pdfPath,String jpgPath){ long start = System.currentTimeMillis(); //pdf路径 InputStream stream = null; try { stream = new FileInputStream(new File(pdfPath));//URLUtil.getStream(url); // 加载解析PDF文件 PDDocument doc = PDDocument.load(stream); PDFRenderer pdfRenderer = new PDFRenderer(doc); PDPageTree pages = doc.getPages(); int pageCount = pages.getCount(); for (int i = 0; i < pageCount; i++) { BufferedImage bim = pdfRenderer.renderImageWithDPI(i, 200); ByteArrayOutputStream os = new ByteArrayOutputStream(); ImageIO.write(bim, "jpg", os); byte[] datas = os.toByteArray(); FileUtils.writeByteArrayToFile(new File(jpgPath),datas); } long end = System.currentTimeMillis(); long time = (end - start) / 1000; System.out.println("pdf转jpg耗时： {}s"+time); }catch (Exception e){ } } /** * base64转jpg * @param val * @param pdfFile * @param jpgFile */ public static void base64ToJPG(String val,String pdfFile,String jpgFile){ base64StringToPDF(val,pdfFile); pdfToJpg(pdfFile,jpgFile); }}
转载于:https://www.cnblogs.com/sung1024/p/11178360.html
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