PDF to PDF / Java Examples

This page contains various examples of using the PDF to PDF API in Java. The examples are complete and fully functional. Read more about how to convert PDF to PDF in Java.

Basic examples
PDF manipulation examples
Spring examples

Basic examples

Multiple PDFs to PDF file

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfFile("/path/to/cover.pdf");
            client.addPdfFile("/path/to/proposal.pdf");
            client.addPdfFile("/path/to/price.pdf");
            client.addPdfFile("/path/to/contact.pdf");

            // Run the conversion and save the result to a file.
            client.convertToFile("offer.pdf");
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
        catch(IOException why) {
            System.err.println("IO Error: " + why);
            throw why;
        }
    }
}

Multiple PDFs to in-memory PDF

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws Pdfcrowd.Error {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfFile("/path/to/cover.pdf");
            client.addPdfFile("/path/to/proposal.pdf");
            client.addPdfFile("/path/to/price.pdf");
            client.addPdfFile("/path/to/contact.pdf");

            // Run the conversion and store the result in the `pdf` variable.
            byte[] pdf = client.convert();

            // at this point the "pdf" variable contains PDF raw data and
            // can be sent in an HTTP response, saved to a file, etc.
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
    }
}

Multiple PDFs to PDF stream

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfFile("/path/to/cover.pdf");
            client.addPdfFile("/path/to/proposal.pdf");
            client.addPdfFile("/path/to/price.pdf");
            client.addPdfFile("/path/to/contact.pdf");

            // Create an output stream for the conversion result
            FileOutputStream outputStream = new FileOutputStream("offer.pdf");

            // run the conversion and write the result to the output stream.
            client.convertToStream(outputStream);

            // Close the output stream.
            outputStream.close();
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
        catch(IOException why) {
            System.err.println("IO Error: " + why);
            throw why;
        }
    }
}

Multiple in-memory PDFs to PDF file

import com.pdfcrowd.*;
import java.io.*;
import java.nio.file.Files;
import java.nio.file.Paths;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/cover.pdf")));
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/proposal.pdf")));
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/price.pdf")));
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/contact.pdf")));

            // Run the conversion and save the result to a file.
            client.convertToFile("offer.pdf");
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
        catch(IOException why) {
            System.err.println("IO Error: " + why);
            throw why;
        }
    }
}

Join 2 in-memory PDFs together with 2 local PDF files to PDF file

import com.pdfcrowd.*;
import java.io.*;
import java.nio.file.Files;
import java.nio.file.Paths;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/cover.pdf")));
            client.addPdfFile("/path/to/proposal.pdf");
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/price.pdf")));
            client.addPdfFile("/path/to/contact.pdf");

            // Run the conversion and save the result to a file.
            client.convertToFile("offer.pdf");
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
        catch(IOException why) {
            System.err.println("IO Error: " + why);
            throw why;
        }
    }
}

Watermark a PDF file

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfFile("/path/to/proposal.pdf");
            client.setPageWatermark("/path/to/watermark.pdf");

            // Run the conversion and save the result to a file.
            client.convertToFile("company_offer.pdf");
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
        catch(IOException why) {
            System.err.println("IO Error: " + why);
            throw why;
        }
    }
}

Linearize a PDF file

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfFile("/path/to/not_linearized.pdf");
            client.setLinearize(true);

            // Run the conversion and save the result to a file.
            client.convertToFile("linearized.pdf");
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
        catch(IOException why) {
            System.err.println("IO Error: " + why);
            throw why;
        }
    }
}

Get info about the current conversion

import com.pdfcrowd.*;
import java.io.*;
import java.nio.file.Files;
import java.nio.file.Paths;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.setDebugLog(true);
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/cover.pdf")));
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/proposal.pdf")));

            // Run the conversion and save the result to a file.
            client.convertToFile("offer.pdf");
            
            // print URL pointing to the debug log for this request.
            System.out.println("Debug log url: " + client.getDebugLogUrl());
            
            // print number of conversion credits remaining in your account.
            System.out.println("Remaining credit count: " + client.getRemainingCreditCount());
            
            // print number of credits consumed for this conversion.
            System.out.println("Consumed credit count: " + client.getConsumedCreditCount());
            
            // print unique identifier assigned to this conversion job.
            System.out.println("Job id: " + client.getJobId());
            
            // print total number of pages in the output document.
            System.out.println("Page count: " + client.getPageCount());
            
            // print size of the output data in bytes.
            System.out.println("Output size: " + client.getOutputSize());
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
        catch(IOException why) {
            System.err.println("IO Error: " + why);
            throw why;
        }
    }
}

PDF manipulation examples

Extract page 3 and all pages from 7 to the end from the PDF file

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfFile("/your-path-to/pdfs/13_pages.pdf");
            client.setAction("extract");
            client.setPageRange("3,7-");

            // Run the conversion and save the result to a file.
            client.convertToFile("output.pdf");
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
        catch(IOException why) {
            System.err.println("IO Error: " + why);
            throw why;
        }
    }
}

Delete the first 3 pages and the 10th page from the PDF file

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfFile("/your-path-to/pdfs/13_pages.pdf");
            client.setAction("delete");
            client.setPageRange("1-3,10");

            // Run the conversion and save the result to a file.
            client.convertToFile("output.pdf");
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
        catch(IOException why) {
            System.err.println("IO Error: " + why);
            throw why;
        }
    }
}

Split the PDF file into two separate files at the 10th page

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");
            client.addPdfFile("/your-path-to/pdfs/13_pages.pdf");
            client.setAction("extract");
            client.setPageRange("1-10");
            client.convertToFile("pages1-10.pdf");
            client.setPageRange("11-");
            client.convertToFile("pages11-end.pdf");
        }
        catch(Pdfcrowd.Error why) {
            System.err.println("PDFCrowd Error: " + why);
            throw why;
        }
        catch(IOException why) {
            System.err.println("IO Error: " + why);
            throw why;
        }
    }
}

Spring examples

Multiple PDFs to PDF in Spring

import java.net.URLEncoder;
import java.io.UnsupportedEncodingException;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.http.ResponseEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import com.pdfcrowd.*;

@Controller
public class DemoController {
    // The recommended method is POST.
    @PostMapping("/")
    public ResponseEntity<byte[]> convert() throws UnsupportedEncodingException {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfFile("/path/to/cover.pdf");
            client.addPdfFile("/path/to/proposal.pdf");
            client.addPdfFile("/path/to/price.pdf");
            client.addPdfFile("/path/to/contact.pdf");

            // Run the conversion and store the result in the `pdf` variable.
            byte[] pdf = client.convert();

            // Set HTTP response headers.
            HttpHeaders headers = new HttpHeaders();
            headers.add("Content-Type", "application/pdf");
            headers.add("Cache-Control", "max-age=0");
            headers.add("Accept-Ranges", "none");
            headers.add("Content-Disposition", "attachment; filename*=UTF-8''" +
                        URLEncoder.encode("offer.pdf", "UTF-8").replace("+", "%20"));

            // Send the result in the HTTP response.
            return new ResponseEntity<>(pdf, headers, HttpStatus.OK);
        }
        catch(Pdfcrowd.Error why) {
            // Send the error in the HTTP response.
            HttpHeaders headers = new HttpHeaders();
            headers.add("Content-Type", "text/plain");
            return new ResponseEntity<>(why.toString().getBytes(), headers, HttpStatus.BAD_REQUEST);
        }
    }
}

Multiple in-memory PDFs to PDF in Spring

import java.net.URLEncoder;
import java.io.UnsupportedEncodingException;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.http.ResponseEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import com.pdfcrowd.*;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.io.IOException;

@Controller
public class DemoController {
    // The recommended method is POST.
    @PostMapping("/")
    public ResponseEntity<byte[]> convert() throws IOException, UnsupportedEncodingException {
        try {
            // Create an API client instance.
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "demo");

            // Configure the conversion.
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/cover.pdf")));
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/proposal.pdf")));
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/price.pdf")));
            client.addPdfRawData(Files.readAllBytes(Paths.get("/path/to/contact.pdf")));

            // Run the conversion and store the result in the `pdf` variable.
            byte[] pdf = client.convert();

            // Set HTTP response headers.
            HttpHeaders headers = new HttpHeaders();
            headers.add("Content-Type", "application/pdf");
            headers.add("Cache-Control", "max-age=0");
            headers.add("Accept-Ranges", "none");
            headers.add("Content-Disposition", "attachment; filename*=UTF-8''" +
                        URLEncoder.encode("offer.pdf", "UTF-8").replace("+", "%20"));

            // Send the result in the HTTP response.
            return new ResponseEntity<>(pdf, headers, HttpStatus.OK);
        }
        catch(Pdfcrowd.Error why) {
            // Send the error in the HTTP response.
            HttpHeaders headers = new HttpHeaders();
            headers.add("Content-Type", "text/plain");
            return new ResponseEntity<>(why.toString().getBytes(), headers, HttpStatus.BAD_REQUEST);
        }
    }
}