Java PDF Generator (Code Example Tutorial)

This article will explore how to use IronPDF to generate new files, extract content, and save PDFs.

IronPDF for Java

IronPDF for Java is built for generating PDF documents or PDF forms from HTML code, whether from a file, HTML string, HTML pages, or URL. It generates PDF files with accuracy, and formatting is also preserved. It is designed in a way that developers find it easy to use.

IronPDF is built on top of the .NET Framework, allowing it to be a versatile tool for generating PDFs in various contexts.

IronPDF provides the following functions for generating and manipulating large documents:

1. The ability to add and extract content from PDFs (text, images, tables, etc.)
2. The ability to control the layout and formatting of the document (e.g., set fonts, colors, margins...)
3. The ability to complete forms and add digital signatures

Steps to Create a PDF File in a Java Application

Prerequisites

To use IronPDF to create a PDF generating tool, the following software needs to be installed on the computer:

1. Java Development Kit - JDK is required for building and running Java programs. If it is not installed, download the latest release from the Oracle Website.
2. Integrated Development Environment - IDE is software that helps write, edit, and debug a program. Download any IDE for Java, e.g., Eclipse, NetBeans, IntelliJ.
3. Maven - Maven is an automation and open-source Java tool that helps download libraries from the Central Maven Repository. Download it from the Apache Maven website.

4. IronPDF - Finally, IronPDF is required to create PDF files in Java. This needs to be added as a dependency in your Java Maven Project. Include the IronPDF artifact along with the slf4j dependency in the pom.xml file as shown below:

   <dependency>
       <groupId>com.ironsoftware</groupId>
       <artifactId>ironpdf</artifactId>
       <version>YOUR_VERSION_HERE</version>
   </dependency>
   <dependency>
       <groupId>org.slf4j</groupId>
       <artifactId>slf4j-api</artifactId>
       <version>YOUR_VERSION_HERE</version>
   </dependency>

   <dependency>
       <groupId>com.ironsoftware</groupId>
       <artifactId>ironpdf</artifactId>
       <version>YOUR_VERSION_HERE</version>
   </dependency>
   <dependency>
       <groupId>org.slf4j</groupId>
       <artifactId>slf4j-api</artifactId>
       <version>YOUR_VERSION_HERE</version>
   </dependency>

   XML

Adding Necessary Imports

First, add the following line at the top of the Java main class source code file to import all the required important class methods from the IronPDF library.

import com.ironsoftware.ironpdf.*;

import com.ironsoftware.ironpdf.*;

Next, configure IronPDF with a valid license key to use its methods. Invoke the setLicenseKey method in the main method.

License.setLicenseKey("Your license key");

License.setLicenseKey("Your license key");

Note: You can get a free trial license key from IronPDF to create and read PDFs.

Generate PDF Documents from HTML String

Creating PDF files from HTML string is very easy and usually takes one or two lines of code to do it. Here, an HTML code is written as a string in a variable and then passed to the renderHtmlAsPdf method found in the PdfDocument class. The following code generates a new PDF document instance:

// Create a string that contains HTML content
String htmlString = "<h1>Hello World!</h1><p>This is an example of an HTML string in Java.</p>";

// Generate a PDF document from the HTML string
PdfDocument pdf = PdfDocument.renderHtmlAsPdf(htmlString);

// Create a string that contains HTML content
String htmlString = "<h1>Hello World!</h1><p>This is an example of an HTML string in Java.</p>";

// Generate a PDF document from the HTML string
PdfDocument pdf = PdfDocument.renderHtmlAsPdf(htmlString);

Now, use the saveAs method to save the generated PDF to a path on your local system:

// Save the generated PDF to the specified path
pdf.saveAs("htmlstring.pdf");

// Save the generated PDF to the specified path
pdf.saveAs("htmlstring.pdf");

The above line of code creates a PDF called "htmlstring.pdf" containing the contents of the HTML string.

The output is as follows:

HTML String to PDF Output

Create PDF Documents from HTML Files

The following code creates a PDF file from an HTML file:

// Convert an HTML file to a PDF document
PdfDocument myPdf = PdfDocument.renderHtmlFileAsPdf("example.html");

// Save the PDF document to the specified path
myPdf.saveAs("html_file.pdf");

// Convert an HTML file to a PDF document
PdfDocument myPdf = PdfDocument.renderHtmlFileAsPdf("example.html");

// Save the PDF document to the specified path
myPdf.saveAs("html_file.pdf");

HTML file code:

<html>
    <head>
        <title>Example HTML File</title>
    </head>
    <body>
        <h1>HTML File Example</h1>
        <p style="font-style:italic;">This is an example HTML file</p>
    </body>
</html>

<html>
    <head>
        <title>Example HTML File</title>
    </head>
    <body>
        <h1>HTML File Example</h1>
        <p style="font-style:italic;">This is an example HTML file</p>
    </body>
</html>

In the above code, the renderHtmlFileAsPdf method generates PDF files from HTML files. This method accepts a string argument containing the path to the HTML file.

IronPDF renders the HTML file elements along with the CSS and JavaScript attached to it, if any. You can see in the output below that the CSS styling is also maintained by IronPDF, and the output is the same as it would have been in a web browser.

HTML File to PDF Output

Generate PDF Files from URL

The renderUrlAsPdf method is used to create PDF files from a web page. It accepts the web page's URL as an argument.

// Generate a PDF document using a URL
PdfDocument urlToPdf = PdfDocument.renderUrlAsPdf("https://ironpdf.com");

// Save the generated PDF to the specified path
urlToPdf.saveAs("urlToPdf.pdf");

// Generate a PDF document using a URL
PdfDocument urlToPdf = PdfDocument.renderUrlAsPdf("https://ironpdf.com");

// Save the generated PDF to the specified path
urlToPdf.saveAs("urlToPdf.pdf");

URL to PDF Output

Additional rendering options can be set to configure PDF generation. You can get more information on the Convert URL to PDF Example Code.

Generating Password Protected PDF Files

IronPDF can be used to create a password-protected PDF file with the SecurityOptions class. All file permissions can be set if you integrate the PDF functionalities of IronPDF. The code goes as follows:

// Create security options and set a user password
SecurityOptions securityOptions = new SecurityOptions();
securityOptions.setUserPassword("shareable");

// Create security options and set a user password
SecurityOptions securityOptions = new SecurityOptions();
securityOptions.setUserPassword("shareable");

setUserPassword is used to set a secure password. The below code sample applies password protection to the PDF document that was created in the URL to PDF example:

// Get the security manager of the PDF document and set the security options
SecurityManager securityManager = urlToPdf.getSecurity();
securityManager.setSecurityOptions(securityOptions);

// Save the protected PDF document to the specified path
urlToPdf.saveAs("protected.pdf");

// Get the security manager of the PDF document and set the security options
SecurityManager securityManager = urlToPdf.getSecurity();
securityManager.setSecurityOptions(securityOptions);

// Save the protected PDF document to the specified path
urlToPdf.saveAs("protected.pdf");

The PDF file is now password protected. Now open the PDF file, and a password option will appear:

Password Protected File

After entering the password correctly, the PDF document will open.

PDF document

More security settings and metadata about the PDF files can be explored in the related Security and Metadata Code Example.

Summary

This article demonstrated the capability of the IronPDF library to create PDFs using multiple methods. IronPDF is a pure Java library and is powerfully built to easily work with PDF files in Java.

IronPDF's Engine makes it easy to create PDFs from various sources such as HTML files, image files, XML documents, Jasper reports, or any other input. It complies with the standard Java printing API, which facilitates document printing, and you can also digitally sign PDF files. IronPDF helps to get all the PDF-related tasks done quickly and easily.

IronPDF is not an open-source Java library. It provides a commercial license which starts from $749. You can also get a free trial of IronPDF to test it in production within your Java applications.