PDF to PDF - Java Guide

This page serves as a guide for using the Pdfcrowd API to join or split PDF files, or update PDF attributes in Java applications. The API is designed for easy use and straightforward integration.

Installation

Download pdfcrowd-5.18.1-java.zip, unzip it and copy pdfcrowd-5.18.1.jar to your CLASSPATH.

Check out other installation options such as Maven or GitHub.

Quick Start

Below are Java examples to help you quickly get started with the API. Explore our additional examples for more insights.

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

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // 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 write 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;
        }
    }
}

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 the API client instance
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // 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 write 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;
        }
    }
}

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

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.PdfToPdfClient client =
                new Pdfcrowd.PdfToPdfClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

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

            // run the conversion and write 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;
        }
    }
}

Authentication

To access the API, you will need to use your Pdfcrowd username and API key. For initial testing, you may use the following demo credentials without registering:

Username: demo
API key: ce544b6ea52a5621fb9d55f8b542d14d

To obtain your personal API credentials, consider starting a free API trial or purchasing the API license.

Error Handling

It is recommended that you implement error handling to catch errors the API may return. Effective error handling is vital as it ensures application stability and provides clearer diagnostics. See the example code below for guidance on implementing error handling, and refer to this list of status codes for more information.

try {
    // call the API 
}
catch(Pdfcrowd.Error why) {
    // print the error
    System.err.println("Pdfcrowd Error: " + why);

    // print the error code
    System.err.println("Pdfcrowd Error Code: " + why.getCode());

    // print the error message
    System.err.println("Pdfcrowd Error Message: " + why.getMessage());
}

Troubleshooting

If you are receiving an error, refer to the API Status Codes for more information.
Utilize setDebugLog() and getDebugLogUrl() to obtain detailed information about the conversion process, including load errors, load times, browser console output, etc.
Consult the FAQ for answers to common questions.
Contact us if you need assistance or if there is a feature you are missing.

API Method Reference

Refer to the PDF to PDF Java Reference for a description of all API methods.