Add or Remove Digital Signatures in PowerPoint Using Java

A digital signature confirms that the document content originates from the signer and has not been changed. In this article, you will learn how to add a digital signature to your PowerPoint documents as well as how to remove all digital signatures using Free Spire.Presentation for Java.

Import JAR Dependency (2 Methods)

● Download the free library and unzip it, and then add the Spire.Presentation.jar file to your project as dependency.

● You can also add the jar dependency to your maven project by adding the following configurations to the pom.xml.

<repositories>
    <repository>
        <id>com.e-iceblue</id>
        <name>e-iceblue</name>
        <url>http://repo.e-iceblue.com/nexus/content/groups/public/</url>
    </repository>
</repositories>
<dependencies>
    <dependency>
        <groupId>e-iceblue</groupId>
        <artifactId>spire.presentation.free</artifactId>
        <version>5.1.0</version>
    </dependency>
</dependencies>

Add a Digital Signature to PowerPoint

• Create an object of Presentation class.
• Load the sample PowerPoint document using Presentation.loadFromFile() method.
• Add a digital signature to the document using Presentation.addDigitalSignature(String pfxPath, String password, String comments, java.util.Date signTime) method.
• Save the result to a .pptx file using Presentation.saveToFile() method.

import com.spire.presentation.FileFormat;
import com.spire.presentation.Presentation;

import java.util.Date;

public class AddDigitalSignature {
    public static void main(String[] args) throws Exception {

        //Create a Presentation object
        Presentation presentation = new Presentation();

        //Load the sample PowerPoint document
        presentation.loadFromFile("sample2.pptx");

        //Add a digital signature
        String pfxPath = "F:\\pfx\\output\\Eric.pfx";
        String password = "111";
        String comment = "Modification is not allowed";
        presentation.addDigitalSignature(pfxPath,password,comment,new Date());

        //Save the result to file
        presentation.saveToFile("output/AddDigitalSignature.pptx", FileFormat.PPTX_2013);
    }
}

Remove all Digital Signaters from PowerPoint

• Create an object of Presentation class.
• Load the sample PowerPoint document using Presentation.loadFromFile() method.
• Determine if the document contains digital signatures using Presentation.isDigitallySigned() method.
• Remove all signatures using Presentation.removeAllDigitalSignatures() method.
• Save the result to a .pptx file using Presentation.saveToFile() method.

import com.spire.presentation.FileFormat;
import com.spire.presentation.Presentation;

public class RemoveDigitalSignature {
    public static void main(String[] args) throws Exception {

        //Create a Presentation object
        Presentation presentation = new Presentation();

        //Load the sample PowerPoint document
        presentation.loadFromFile("C:\\Users\\Administrator\\IdeaProjects\\PPT\\output\\AddDigitalSignature.pptx");

        //Determine if the document is digitally signed
        if (presentation.isDigitallySigned() == true)
        {
            //Remove all digital signatures
            presentation.removeAllDigitalSignatures();
        }

        //Save the result to file
        presentation.saveToFile("output/RemoveDigitalSignature.pptx", FileFormat.PPTX_2013);
    }
}