Java利用Spire.PDF for Java实现在PDF中添加或删除数字签名

  <repositories>
    <repository>
        <id>com.e-iceblue</id>
        <name>e-iceblue</name>
        <url>https://repo.e-iceblue.cn/repository/maven-public/</url>
    </repository>
</repositories>
<dependencies>
    <dependency>
        <groupId>e-iceblue</groupId>
        <artifactId>spire.pdf</artifactId>
        <version>11.10.3</version>
    </dependency>
</dependencies>

import com.spire.pdf.graphics.*;
import com.spire.pdf.security.GraphicMode;
import com.spire.pdf.security.PdfCertificate;
import com.spire.pdf.security.PdfCertificationFlags;
import com.spire.pdf.security.PdfSignature;

import java.awt.*;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;

public class AddDigitalSignature {

    public static void main(String[] args) {

        //加载PDF文档
        PdfDocument doc = new PdfDocument();
        doc.loadFromFile("C:\Users\Administrator\Desktop\sample.pdf");

        //加载pfx证书
        PdfCertificate cert = new PdfCertificate("C:\Users\Administrator\Desktop\gary.pfx", "e-iceblue");

        //添加数字签名，设置其位置和大小
        PdfSignature signature = new PdfSignature(doc, doc.getPages().get(0), cert, "MySignature");
        Rectangle2D rect = new Rectangle2D.Float();
        rect.setFrame(new Point2D.Float((float) doc.getPages().get(0).getActualSize().getWidth() - 340, (float) doc.getPages().get(0).getActualSize().getHeight() - 150), new Dimension(270, 100));
        signature.setBounds(rect);

        //设置签名为图片加文本模式
        signature.setGraphicMode(GraphicMode.Sign_Image_And_Sign_Detail);

        //设置签名的内容
        signature.setNameLabel("签字者：");
        signature.setName("Gary");
        signature.setContactInfoLabel("联系电话：");
        signature.setContactInfo("02881705109");
        signature.setDateLabel("日期：");
        signature.setDate(new java.util.Date());
        signature.setLocationInfoLabel("地点：");
        signature.setLocationInfo("成都");
        signature.setReasonLabel("原因：");
        signature.setReason("我是文档所有者");
        signature.setDistinguishedNameLabel("DN: ");
        signature.setDistinguishedName(signature.getCertificate().get_IssuerName().getName());
        signature.setSignImageSource(PdfImage.fromFile("C:\Users\Administrator\Desktop\logo-2.png"));

        //设置签名的字体
        signature.setSignDetailsFont(new PdfTrueTypeFont(new Font("宋体", Font.PLAIN, 12)));

        //设置文档权限为禁止更改
        signature.setDocumentPermissions(PdfCertificationFlags.Forbid_Changes);
        signature.setCertificated(true);

        //保存文档
        doc.saveToFile("output/AddSignature.pdf");
        doc.close();
    }
}

import com.spire.pdf.PdfDocument;
import com.spire.pdf.widget.PdfFieldWidget;
import com.spire.pdf.widget.PdfFormWidget;
import com.spire.pdf.widget.PdfSignatureFieldWidget;

public class RemoveSignature {

    public static void main(String[] args) {

        //创建PdfDocument对象 
        PdfDocument pdf = new PdfDocument();

        //加载PDF文档
        pdf.loadFromFile("C:\Users\Administrator\Desktop\Signature.pdf");

        //从文档获取form widget集合
        PdfFormWidget widgets = (PdfFormWidget) pdf.getForm();

        //遍历集合中的每一个元素
        for (int i = 0; i < widgets.getFieldsWidget().getList().size(); i++)
        {
            //获取指定widget
            PdfFieldWidget widget = (PdfFieldWidget)widgets.getFieldsWidget().getList().get(i);

            //判断widget是否为PdfSignatureFieldWidget
            if (widget instanceof PdfSignatureFieldWidget)
            {
                //删除数字签名widget
                widgets.getFieldsWidget().remove(widget);
            }
        }

        //保存文档
        pdf.saveToFile("RemoveSignature.pdf");
    }
}