PDF to PDF Java Examples

These examples demonstrate common PDF to PDF API workflows in Java.

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);
        }
    }
}