java 给pdf加水印-蒲公英云

java 给pdf加水印

1、加入依赖

<!--pdf加水印依赖-->
<dependency>
    <groupId>com.itextpdf</groupId>
    <artifactId>itext-asian</artifactId>
    <version>5.2.0</version>
</dependency>
<dependency>
    <groupId>com.itextpdf</groupId>
    <artifactId>itextpdf</artifactId>
    <version>5.4.3</version>
</dependency>

2、上代码

import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Image;
import com.itextpdf.text.pdf.PdfContentByte;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfStamper;
/** * 将图片印到授权pdf中，若成功返回true，失败则返回false * @param imgBytes 图片字节码 * @param pdfTemplatePath pdf存放路径 * @param savePath 合成后pdf保存路径 * @return */
  public boolean pdfAddWatermark(byte[] imgBytes, String pdfTemplatePath, String savePath) throws BusinessException { 
      PdfReader reader = null;
      PdfStamper stamp = null;
      Image img = null;
      try { 
          String filePath = savePath.substring(0, savePath.lastIndexOf('/'));
          File file = new File(filePath);
          if(!file.exists()) { 
              file.mkdirs();
          }
          reader = new PdfReader(pdfTemplatePath, "PDF".getBytes());
          stamp = new PdfStamper(reader, new FileOutputStream(savePath));  //加了水印后要输出的路径
          img = Image.getInstance(imgBytes);
          int pageSize = reader.getNumberOfPages();          //原pdf文件的总页数
          img.setAbsolutePosition(350, 300);          //印章位置
          img.scalePercent(20);                           //印章大小
          for (int i = 1; i <= pageSize; i++) { 
// PdfContentByte under = stamp.getUnderContent(i); //背景被覆盖
              //文字被覆盖
              PdfContentByte under = stamp.getOverContent(i);
              //添加电子印章
              under.addImage(img);
          }
          return true;
      } catch (Exception e) { 
          e.printStackTrace();
      } finally { 
          try { 
              stamp.close();
              reader.close();
          } catch (DocumentException e) { 
              e.printStackTrace();
          } catch (IOException e) { 
              e.printStackTrace();
          }
      }
  }