Manually integrate Nutrient Java SDK for PDF processing

This guide helps you gain precise control over Nutrient Java SDK integration by manually adding files and managing all dependencies for powerful PDF functionalities. By the end, you’ll be able to load a PDF document into your application using the Nutrient Java API.

Use the manual integration method only when absolutely necessary; otherwise, we recommend referring to the automatic method of integrating Nutrient Java library for detailed instructions.

Select the build system you’re using:

Gradle
Maven

If you’re using the Gradle(opens in a new tab) build system, a good example of how to integrate the Nutrient Java library can be seen in the Catalog example distributed in the downloaded ZIP.

Follow the instructions below for manual Gradle integration:

Create a folder within your project named libs.
Download the latest release(opens in a new tab).
In the downloaded ZIP file, there will be a JAR file, pspdfkit-{% $LATEST_VERSIONS.JAVA %}.jar. Copy this JAR file into the libs folder you just created.
In your project’s build.gradle folder, add a dependency to the copied JAR file (replace the wildcards with the version number):
```
dependencies {
    ...
    implementation files('libs/pspdfkit-1.7.1.jar')

    // Required by PSPDFKit.
    implementation 'org.json:json:20180813'
    implementation 'org.apache.httpcomponents:httpclient:4.5.9'
    ...
}
```
Now your Gradle project will depend upon the JAR file. More information about declaring dependencies can be found in the Gradle documentation(opens in a new tab).
Add the OCR dependency (optional). This is only necessary if you plan to use the OCR feature. To do that, a separate package, libraries-java-ocr, is required. Download the latest release(opens in a new tab), which contains the OCR package.

To use the Nutrient Java library with Maven(opens in a new tab), it’s necessary to install the Nutrient (previously PSPDFKit) JAR to a Maven repository. Only when this is done can it be a reference for a Maven project.

Download the latest release(opens in a new tab).
Extract the files from PSPDFKit-Java-binary-{% $LATEST_VERSIONS.JAVA %}.zip into a known location.
Within your project, using mvn on the command line, add the Nutrient JAR to a repository, replacing both the version (where necessary) and the path to the JAR and POM (extracted from PSPDFKit-Java-binary-{% $LATEST_VERSIONS.JAVA %}.zip):
Terminal window
```
mvn install:install-file -Dfile=/path/to/jar/pspdfkit-*.*.*.jar -DpomFile=/path/to/pom/pspdfkit-pom.xml
```
This will install the JAR to a local repository. It’s also possible to publish this JAR remotely; see the Maven guides(opens in a new tab) if this is a requirement.
Add the Nutrient Java library as a dependency of your project. In your project’s pom.xml, add the following, replacing the version with the target version:
```
...
<dependencies>
    <dependency>
   <groupId>com.pspdfkit.api</groupId>
   <artifactId>pspdfkit</artifactId>
   <version>1.7.1</version>
    </dependency>
</dependencies>
...
```
Now your Maven project will depend on the Nutrient JAR published to the chosen repository.
Add the OCR dependency (optional). This is only necessary if you plan to use the OCR feature. To do that, a separate package, libraries-java-ocr, is required. Download the latest release(opens in a new tab), which contains the OCR package.

Using the Nutrient Java library

Now that the Nutrient library is added, you can use the SDK in your application. You need to initialize the SDK prior to calling any other method. Use the initializeTrial method if you haven’t yet bought a license key, or the initialize method if you have a key:

Java
Kotlin

public void initializePSPDFKit() throws PSPDFKitInitializeException {
 PSPDFKit.initializeTrial();
}

@Throws(PSPDFKitInitializeException::class)
fun initializePSPDFKit() : Void {
 PSPDFKit.initializeTrial();
}

Next, load a document:

Java
Kotlin

File file = new File("path/to/document.pdf");
PdfDocument document = PdfDocument.open(new FileDataProvider(file));

val file = File("path/to/document.pdf")
val document = PdfDocument.open(FileDataProvider(file))

Once you have a document loaded, you can use the rest of the library. See the API docs and guides for more information, or try out the Catalog examples (see below).

Building and running the Catalog app

The Nutrient library comes with an example application called the Catalog app, which contains many useful examples for exploring the different features of Nutrient. You can find the app in the Example folder of the SDK ZIP file(opens in a new tab).

To build and run the Catalog app, follow the instructions below.

Download the latest release(opens in a new tab).
Extract PSPDFKit-Libraries-java_binary-{version}.zip to your desired location and cd into the root of its directory.
cd into the Catalog (cd catalog).
Build and run the Catalog application:
Terminal window
```
./gradlew runJava
```

Download the latest release(opens in a new tab).
Extract PSPDFKit-Libraries-java_binary-{version}.zip to your desired location and cd into the root of its directory.
cd into the Catalog (cd catalog).
Build and run the Catalog application:
Terminal window
```
./gradlew runJava
```

Download the latest release(opens in a new tab).
Extract PSPDFKit-Libraries-java_binary-{version}.zip to your desired location and cd into the root of its directory.
cd into the Catalog (cd catalog).
Build and run the Catalog application:
Terminal window
```
gradlew.bat runJava
```