Merging PDFs

In many business workflows, there’s a need to combine multiple documents into a single PDF file. Whether it’s consolidating reports, combining scanned pages with digital documents, or assembling documentation packages, PDF merging is a fundamental requirement for document management systems.

PDF merging enables organizations to create comprehensive document packages from various sources while maintaining the original formatting and quality of each component. This capability is essential for creating unified deliverables, reducing file management complexity, and improving document distribution efficiency.

For teams working with mixed document formats, the ability to merge different file types into a single PDF streamlines workflows and ensures all related content is kept together in a universally accessible format.

Streamlining document assembly with our Java SDK

What makes this feature particularly valuable is how effortlessly it can be implemented using our SDK. With just a few lines of code, developers can merge multiple documents from different formats into a single PDF. Whether you’re building a document assembly system or adding merge functionality to an existing application, our SDK delivers reliable merging capabilities right out of the box.

Preparing the project

Start by specifying a package name and importing the required classes:

package io.nutrient.Sample;

import io.nutrient.sdk.*;
import io.nutrient.sdk.exceptions.NutrientException;
import io.nutrient.sdk.editors.*;
import io.nutrient.sdk.exporters.*;

Then create the main function and specify that it can throw a NutrientException. This exception could also be caught in the program logic for custom error management, but this is left as an exercise for the reader:

public class PDFMerging {
    public static void main(String[] args) throws NutrientException {

Once the inherent setup from a Java application is done, focus on what’s specific to our SDK.

The first step is to initialize the SDK by registering the license. This needs to be done only once during the application’s lifetime and must occur before executing any additional logic:

        License.registerKey("");

Merging multiple documents

With the SDK successfully initialized, you can begin working with the classes it offers. This guide demonstrates how to merge documents from different formats. Start by opening a Word document that will serve as the base for your merged PDF.

The SDK supports multiple integration methods, enabling flexibility in how you connect with your application. The source file can be specified either via a file path or a stream. This guide uses file paths:

        try (Document document = Document.open("input.docx")) {

Create a PdfEditor instance to work with the document:

            PdfEditor editor = PdfEditor.edit(document);

Appending additional documents

Now you can append another document to your base document. The SDK handles format conversion automatically, so you can merge PDFs with Word documents seamlessly:

            try (Document document2 = Document.open("input.pdf")) {
                editor.appendDocument(document2);
            }

Saving the merged result

After appending all desired documents, save the changes and export the final merged PDF:

            editor.save();
            editor.close();

            document.export("output_merged_documents.pdf", new PdfExporter());
        }
    }
}

That’s it! You’ve successfully merged multiple documents into a single PDF file.

Error handling

Nutrient Java SDK handles errors with exception handling. The methods presented in this guide throw a NutrientException in case of failure. This helps with troubleshooting and implementing error handling logic.

Conclusion

That’s all it takes to merge multiple documents into a single PDF! The SDK handles format conversion and document assembly seamlessly, enabling you to create unified PDF packages from various document sources with minimal code. You can also download this ready-to-use sample package, fully configured to help you dive into the Java SDK right away.