--添加依賴
<!-- https://mvnrepository.com/artifact/org.apache.pdfbox/pdfbox -->
<dependency>
<groupId>org.apache.pdfbox</groupId>
<artifactId>pdfbox</artifactId>
<version>2.0.12</version>
</dependency>
--最佳實踐
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 {
/**
* 將base64字符串轉換為PDF在顯示到頁面中
* @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寫進輸出流里
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");
// 設置打印PDF的文件名
String fileName = "社保證明文件.pdf";
fileName = new String(fileName.getBytes("UTF-8"), "ISO-8859-1");
httpServletResponse.setHeader("Content-Disposition", "filename=" + fileName);
sos = httpServletResponse.getOutputStream();
baos.writeTo(sos); //byte輸出流寫入servlet輸出流
sos.flush();
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
sos.close();
baos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* 將base64編碼轉換成PDF
* @param base64String
* 1.使用BASE64Decoder對編碼的字符串解碼成字節數組
* 2.使用底層輸入流ByteArrayInputStream對象從字節數組中獲取數據；
* 3.建立從底層輸入流中讀取數據的BufferedInputStream緩沖輸出流對象；
* 4.使用BufferedOutputStream和FileOutputSteam輸出數據到指定的文件中
*/
public static void base64StringToPDF(String base64String, String pdfPath/*File file*/){
File file = new File(pdfPath);// 將原來參數修改為字符串
BASE64Decoder decoder = new BASE64Decoder();
BufferedInputStream bin = null;
FileOutputStream fout = null;
BufferedOutputStream bout = null;
try {
//將base64編碼的字符串解碼成字節數組
byte[] bytes = decoder.decodeBuffer(base64String);
//創建一個將bytes作為其緩沖區的ByteArrayInputStream對象
ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
//創建從底層輸入流中讀取數據的緩沖輸入流對象
bin = new BufferedInputStream(bais);
//創建到指定文件的輸出流
fout = new FileOutputStream(file);
//為文件輸出流對接緩沖輸出流對象
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);
}
//刷新此輸出流並強制寫出所有緩沖的輸出字節，必須這行代碼，否則有可能有問題
bout.flush();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
bout.close();
fout.close();
bin.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* PDF轉換為Base64編碼
* @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);
}
//刷新此輸出流並強制寫出所有緩沖的輸出字節
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轉jpg
* @param pdfPath
* @param jpgPath
*/
public static void pdfToJpg(String pdfPath,String jpgPath){
long start = System.currentTimeMillis();
//pdf路徑
InputStream stream = null;
try {
stream = new FileInputStream(new File(pdfPath));//URLUtil.getStream(url);
// 加載解析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轉jpg耗時： {}s"+time);
}catch (Exception e){
}
}
/**
* base64轉jpg
* @param val
* @param pdfFile
* @param jpgFile
*/
public static void base64ToJPG(String val,String pdfFile,String jpgFile){
base64StringToPDF(val,pdfFile);
pdfToJpg(pdfFile,jpgFile);
}
}