Java merge and split PDF files

This article shows how to use Spire.PDF for Java to programmatically merge many single PDF files into a whole PDF and split a PDF file into separate PDF files in Java applications.

Installing Spire.pdf.jar

If you create a Maven project, you can easily import the jar in your application using the following configurations. For non-Maven projects, download the jar file from this link and manually add it as a dependency in your application.

<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.pdf</artifactId>
        <version>4.4.5</version>
    </dependency>
</dependencies>

Merge PDF documents by stream. Input the three PDF documents by stream and then use PdfDocument.mergeFiles(streams)methods to merge the PDF documents into one PDF document.

import com.spire.pdf.*;
import java.io.*;

public class mergePDF {

        public static void main(String[] args) throws Exception {
            String outputFile = "output/mergeFilesByStream.pdf";

            FileInputStream stream1 = new FileInputStream(new File("C:\\Users\\Administrator\\Desktop\\Sample1.pdf"));
            FileInputStream stream2 = new FileInputStream(new File("C:\\Users\\Administrator\\Desktop\\Sample2.pdf"));
            FileInputStream stream3 = new FileInputStream(new File("C:\\Users\\Administrator\\Desktop\\Sample3.pdf"));

            InputStream[] streams = new FileInputStream[]{stream1, stream2, stream3};

            //Merge files by stream
            PdfDocumentBase doc = PdfDocument.mergeFiles(streams);

            //Save the file
            doc.save(outputFile);
            doc.close();

        }
    }

Spire.PDF also supports to load the PDF documents from file and select the first PdfDocument for the purpose of merging the second and third PDF file to it.

import com.spire.pdf.*;
import java.io.IOException;

public class mergePDF {
    public static void main(String[] args) throws IOException {

        //Pdf document list
        String[] files = new String[]
                {
                        "Sample1.pdf",
                        "Sample2.pdf",
                        "Sample3.pdf",
                };
        String outputFile = "output/MergeDocument.pdf";

        //Open pdf documents
        PdfDocument[] docs = new PdfDocument[files.length];
        PdfDocument doc = new PdfDocument();
        for (int i = 0; i < files.length; i++) {
            docs[i] = new PdfDocument();
            docs[i].loadFromFile(files[i]);
        }
        //Append document
        docs[0].appendPage(docs[1]);

        //import pages
        for (int i = 0; i < docs[2].getPages().getCount(); i = i + 1) {
            docs[0].insertPage(docs[2], i);
        }

        //Save pdf file.
        docs[0].saveToFile(outputFile);
        doc.close();
            }
        }

Split every page of the PDF into a separate file by PdfDocument.split() method offered by Spire.PDF for Java.

import com.spire.pdf.*;
import java.io.IOException;

public class splitPDF {
    public static void main(String[] args) throws IOException {
        PdfDocument doc = new PdfDocument();
        doc.loadFromFile("MergeDocument.pdf");

        //Split every page of the PDF into a separate file
        doc.split("output/splitDocument-{0}.pdf", 0);
        doc.close();
    }
}

Split the PDF into multiple files by a range of pages. We will split a single PDF file into two PDFs. One with 2 pages and the other with 4 pages.

import com.spire.pdf.*;
import java.io.IOException;
import com.spire.pdf.graphics.PdfMargins;

import java.awt.geom.Point2D;

public class splitPDF {
    public static void main(String[] args) throws IOException {
        //Load the PDF file
        PdfDocument doc = new PdfDocument();
        doc.loadFromFile("MergeDocument.pdf");

        //Create a new PDF file
        PdfDocument newDoc1 = new PdfDocument();
        PdfPageBase page;

        //Add 2 pages to the new PDF, and draw the content of page 1-2 of the original PDF to the new added pages
        for(int i = 0;i<2;i++)
        {
            page = newDoc1.getPages().add(doc.getPages().get(i).getSize(), new PdfMargins(0));
            doc.getPages().get(i).createTemplate().draw(page, new Point2D.Float(0,0));
        }

        //Save the file
        newDoc1.saveToFile("Output/Doc1.pdf");

        //Create another PDF file
        PdfDocument newDoc2 = new PdfDocument();

        //Add 4 pages to the new PDF, and draw the content of page 3-6 of the original PDF to the new added pages
        for(int i = 2;i<6;i++)
        {
            page = newDoc2.getPages().add(doc.getPages().get(i).getSize(), new PdfMargins(0));
            doc.getPages().get(i).createTemplate().draw(page, new Point2D.Float(0,0));
        }

        //Save the document to file
        newDoc2.saveToFile("Output/Doc2.pdf");
    }
}