Cómo Crear PDF Desde Plantilla en Java

IronPDF

IronPDF is a Java library that is developed and maintained by Iron Software. It provides an easy-to-use interface that abstracts away many of the complexities of PDF generation, allowing developers to focus on the content of their PDFs rather than the details of how the files are generated. IronPDF also provides a range of features that make it easy to work with PDF templates, fillable forms, and digital signatures.

This tutorial will walk you through the steps required to create a PDF file from a template using IronPDF in Java.

The first step is to create a project.

Step 1: Create a new Java project

Here are the steps to create a new Java project using IntelliJ IDEA:

1. Open IntelliJ IDEA and select "Create New Project" from the welcome screen or from the "File" menu.
2. Select "Java" from the left-hand menu and choose the JDK version that you want to use for your project. Click "Next".
3. Choose a project name and location for your project, and select the project type. You can choose from a number of different project types, such as "Java Application", "Java Library", or "JavaFX Application". Click "Next".
4. Configure the project settings. You can specify the project SDK, project language level, and other settings. You can also choose to create a module or select an existing one. Click "Next".
5. Choose the project template. You can choose to create a blank project, a project with a sample code, or import an existing project. Click "Finish".

Create new Java Project Using IntelliJ IDEA

Step 2: Add the IronPDF Library to Your Project

The second step is to add the IronPDF library to your Java project using an XML file. You can do this by adding the following dependency to your project's pom.xml file:

<!-- Add this dependency to use IronPDF in your Java project -->
<dependency>
    <groupId>com.ironsoftware</groupId>
    <artifactId>ironpdf</artifactId>
    <version>VERSION_NUMBER</version> <!-- Specify the version number -->
</dependency>

<!-- Add this dependency to use IronPDF in your Java project -->
<dependency>
    <groupId>com.ironsoftware</groupId>
    <artifactId>ironpdf</artifactId>
    <version>VERSION_NUMBER</version> <!-- Specify the version number -->
</dependency>

Step 3: Create the PDF Template

Next, you need to create a PDF template that you will use to generate your PDF file. You can create your PDF template using any PDF editor. The template can include placeholders that will be replaced with dynamic data at runtime.

Suppose a use case where a number of certificates are issued to 50 students. Now it is a very hectic task to create separate certificates for each user. So a template is used and just change a name using this demo program as demonstrated below.

Certificate Template image instance

Step 4: Create PDF Documents from Template

After creating the PDF template certificate, the first step is to load it into the Java application. The IronPDF PdfDocument class is used to load the PDF template into memory. Here is an example code snippet that shows how to load a PDF template using IronPDF:

// Load the PDF template into memory using IronPDF
PdfDocument pdfDoc = PdfDocument.fromFile(Paths.get("CERTIFICATE.pdf"));

// Load the PDF template into memory using IronPDF
PdfDocument pdfDoc = PdfDocument.fromFile(Paths.get("CERTIFICATE.pdf"));

Now, let's write a code example that will create 5 certificates based on the given template.

import com.ironsoftware.ironpdf.PageSelection;
import com.ironsoftware.ironpdf.PdfDocument;

import java.io.IOException;
import java.nio.file.Paths;

public class CertificateGenerator {
    public static void main(String[] args) throws IOException {
        // Array of student names
        String[] studentNames = {"Georgia Wade", "Juliet Dave", "Olive Seth", "Miles Jorg", "Oscar Den"};

        // Iterate through each student's name
        for (String name : studentNames) {
            // Load the PDF template
            PdfDocument pdfDoc = PdfDocument.fromFile(Paths.get("CERTIFICATE.pdf"));

            // Replace the placeholder text with the student's name
            pdfDoc.replaceText(PageSelection.firstPage(), "Recipient Name", name);

            // Save the new PDF with the student's name as the file name
            pdfDoc.saveAs(Paths.get("Certificate/" + name + ".pdf"));
        }
    }
}

import com.ironsoftware.ironpdf.PageSelection;
import com.ironsoftware.ironpdf.PdfDocument;

import java.io.IOException;
import java.nio.file.Paths;

public class CertificateGenerator {
    public static void main(String[] args) throws IOException {
        // Array of student names
        String[] studentNames = {"Georgia Wade", "Juliet Dave", "Olive Seth", "Miles Jorg", "Oscar Den"};

        // Iterate through each student's name
        for (String name : studentNames) {
            // Load the PDF template
            PdfDocument pdfDoc = PdfDocument.fromFile(Paths.get("CERTIFICATE.pdf"));

            // Replace the placeholder text with the student's name
            pdfDoc.replaceText(PageSelection.firstPage(), "Recipient Name", name);

            // Save the new PDF with the student's name as the file name
            pdfDoc.saveAs(Paths.get("Certificate/" + name + ".pdf"));
        }
    }
}

Following are the output logs:

Output

The above code creates an array of student names and then uses the IronPDF library to replace a placeholder text in a pre-existing PDF template with each student's name and then saves a new copy of the PDF with the student's name as the file name.

Here's how the code works:

1. The studentNames array is defined and initialized with five student names.
2. The for loop iterates through each name in the studentNames array.
3. The PdfDocument.fromFile method loads the PDF template file named "CERTIFICATE.pdf" into a PdfDocument object.
4. The PdfDocument.replaceText method is used to replace the text "Recipient Name" in the PDF template with the current student's name.
5. The PdfDocument.saveAs method saves the modified PDF file with the student's name as the file name in the "Certificate" directory.
6. The loop continues until all student names have been processed.

In this way, multiple certificates are generated, each with a unique student name, based on a single PDF template. The same approach can be used to generate PDF documents with any template.

Certificate Output File

Following is the certificate generated by this demo program.

Certificate Output

Step 5: Create PDF Template from HTML Template

In this example, the HTML file will be used to create a PDF template and then will use that template to generate a PDF document.

This is the HTML file for demonstrating in the example.

HTML Output

Consider the following code example to create a new document from the given HTML format.

import com.ironsoftware.ironpdf.PdfDocument;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class HtmlToPdfExample {
    public static void main(String[] args) throws IOException {
        // Path to the HTML template
        Path fileName = Path.of("D:\\index.html");

        // Dynamic data to replace placeholders in the template
        String userName = "Mike";
        String title = "Sample PDF File";
        String body = "This is the body of our template PDF";

        // Read the HTML file content as a string
        String htmlStr = Files.readString(fileName);

        // Replace placeholders with actual data
        htmlStr = htmlStr.replace("{UserName}", userName);
        htmlStr = htmlStr.replace("{Title}", title);
        htmlStr = htmlStr.replace("{message}", body);

        // Render the HTML as a PDF document using IronPDF
        PdfDocument pdfDoc = PdfDocument.renderHtmlAsPdf(htmlStr);

        // Save the generated PDF document in the specified directory
        pdfDoc.saveAs(Paths.get("htmlTemplate/" + userName + ".pdf"));
    }
}

import com.ironsoftware.ironpdf.PdfDocument;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class HtmlToPdfExample {
    public static void main(String[] args) throws IOException {
        // Path to the HTML template
        Path fileName = Path.of("D:\\index.html");

        // Dynamic data to replace placeholders in the template
        String userName = "Mike";
        String title = "Sample PDF File";
        String body = "This is the body of our template PDF";

        // Read the HTML file content as a string
        String htmlStr = Files.readString(fileName);

        // Replace placeholders with actual data
        htmlStr = htmlStr.replace("{UserName}", userName);
        htmlStr = htmlStr.replace("{Title}", title);
        htmlStr = htmlStr.replace("{message}", body);

        // Render the HTML as a PDF document using IronPDF
        PdfDocument pdfDoc = PdfDocument.renderHtmlAsPdf(htmlStr);

        // Save the generated PDF document in the specified directory
        pdfDoc.saveAs(Paths.get("htmlTemplate/" + userName + ".pdf"));
    }
}

The above code reads the content of an HTML file, replaces placeholders in the HTML file with dynamic data, renders the HTML as a PDF document using the IronPDF library, and saves the generated PDF document in a specific directory.

Here's a step-by-step explanation of what the code does:

1. The code begins by creating a Path object that points to an HTML file on the local file system. In this case, the file is located at "D:\index.html".
2. Three variables are declared and initialized with some sample data: userName, title, and body.
3. The content of the HTML file is read into a string variable called htmlStr using the Files.readString method.
4. The String.replace method is used to replace three placeholders ({UserName}, {Title}, and {message}) in the HTML file with the corresponding dynamic data.
5. The PdfDocument.renderHtmlAsPdf method is called with the modified HTML string as an argument to render the HTML as a PDF document. The resulting PDF document is stored in a PdfDocument object called pdfDoc.
6. The pdfDoc.saveAs method is called to save the generated PDF document to a directory called "htmlTemplate" on the local file system, with the filename constructed from the userName variable.

Output

In this way, it is easy to create PDF files from HTML templates programmatically.

It is possible to replace this watermark by getting a free trial or purchasing a commercial license.

Conclusion

This article explored how to use IronPDF for Java to generate PDF files. IronPDF provides a simple and powerful interface that allows you to create and manipulate PDF files with ease. With IronPDF, you can easily create professional-looking PDF documents that can be used for a variety of purposes, such as generating reports, invoices, and other types of documents.

IronPDF is also highly customizable, with options to control the appearance and layout of PDF files. Developers can specify page margins, font sizes, colors, and other properties to create PDF files that match their specific requirements.

Overall, IronPDF is a powerful and flexible library for PDF generation in Java. With its easy-to-use interface and wide range of features, IronPDF is a great choice for any application that requires PDF generation.

Download IronPDF for Java, the software product.