PDF is one of the widely used document formats because of its consistent layout across heterogeneous platforms. Furthermore, it can be displayed in desktop-based software applications as well as the web browsers at the same time. The support of web browsers make PDF files capable of running JavaScript. In this article, you will learn how to add or remove JavaScript in PDF files programmatically in Java.
- Java API to Add or Remove JavaScript in PDF
- Add JavaScript to PDF Files
- Add Document Level JavaScript in a PDF File
- Remove JavaScript from a PDF File
Java API to Add or Remove JavaScript in PDF Files
Aspose.PDF for Java is an amazing API that provides a range of features for PDF generation and manipulation. With this API, you can seamlessly create new and manipulate the existing PDF files. We will use this API to add and remove JavaScript in PDF files. You can download the API or install it using the following Maven configurations.
Repository:
<repository>
<id>AsposeJavaAPI</id>
<name>Aspose Java API</name>
<url>https://repository.aspose.com/repo/</url>
</repository>
Dependency:
<dependency>
<groupId>com.aspose</groupId>
<artifactId>aspose-pdf</artifactId>
<version>22.4</version>
</dependency>Add JavaScript to PDF Files in Java
PDF files support Acrobat JavaScript, which is based on the core of JavaScript version 1.5 of ISO-16262, formerly known as ECMAScript. It is an object-oriented scripting language developed by Netscape Communications. Before proceeding to add JavaScript to PDF files, let’s have a look at the differences between Acrobat JavaScript and HTML JavaScript which is used in web browsers.
- Acrobat JavaScript does not have access to objects within an HTML page. Similarly, HTML JavaScript cannot access objects within a PDF file.
- HTML JavaScript is able to manipulate objects such as Window. However, Acrobat JavaScript cannot access these particular objects but it can manipulate PDF-specific objects.
The following are the steps to add JavaScript to a PDF file.
- Load the PDF file using the Document class.
- Create an instance of JavascriptAction class and initialize it with the desired script.
- Assign JavascriptAction object to Document.setOpenAction() method for document level JavaScript.
- To add page level JavaScript, use setOnClose() and setOnOpen() methods.
- Save PDF using Document.save(String) method.
The following code sample shows how to add JavaScript to a PDF file.
Add Document Level JavaScript in a PDF in Java
You can also add JavaScript to the document level using Document.getJavaScript().set_Item() method. The following are the steps to add JavaScript to the document level in Java.
- Load the PDF file using Document class.
- Use Document.getJavaScript().set_Item() method to add JavaScript functions.
- Save PDF using Document.save(String) method.
The following code sample shows how to add JS script to a PDF file in Java.
Remove JavaScript from a PDF File in Java
The following are the steps to remove JavaScript from a PDF file in Java.
- Load the PDF file using Document class.
- Remove desired JavaScript by its key using Document.getJavaScript().remove(String) method.
- Save PDF using Document.save(String) method.
The following code sample shows how to remove JavaScript from a PDF file in Java.
Get a Free License
You can get a free temporary license in order to use Aspose.PDF for Java without evaluation limitations.
Conclusion
In this article, you have learned how to add JavaScript to PDF files in Java. Furthermore, you have seen how to remove JavaScript from a PDF file programmatically. Besides, you can explore more about Java PDF API using the documentation. In case you would have any questions or queries, you can contact us via our forum.
