java

Payflow Java SDK

A Java SDK for easy integration with the PayPal Payflow Gateway. Requires Java 11 or newer.

Note: v5 contains breaking changes from v4. Review the CHANGELOG before upgrading an existing integration.

Requirements

• Java 11+ (LTS releases recommended; Java 8 also works — set maven.compiler.release=8 in pom.xml)
• Apache Maven 3.6+ (for building)

Quick Start

Step 1 — Configure credentials

Credentials are read at runtime — never hardcoded. You have two options:

Option A — Environment variables (recommended for CI/CD and shared machines):

export PAYFLOW_USER=your_user
export PAYFLOW_VENDOR=your_vendor
export PAYFLOW_PARTNER=PayPal
export PAYFLOW_PASSWORD=your_password

On Windows (PowerShell):

$env:PAYFLOW_USER     = "your_user"
$env:PAYFLOW_VENDOR   = "your_vendor"
$env:PAYFLOW_PARTNER  = "PayPal"
$env:PAYFLOW_PASSWORD = "your_password"

Option B — Properties file (simple local use):

Create java/payflow.properties and fill in your account details:

PayflowUser=your_user
PayflowVendor=your_vendor
PayflowPartner=PayPal
PayflowPassword=your_password

This file is listed in .gitignore and will never be committed.

Priority: Environment variables take precedence over payflow.properties. If any env var is missing, the file is used as a fallback. If neither is available, the sample prints an error and exits.

Step 2 — Run the sample

Once credentials are set in payflow.properties, run:

# Windows (PowerShell)
cd java
.\run-sample.ps1

# Linux / macOS / Git Bash
cd java
./run-sample.sh

REM Windows (Command Prompt)
cd java
run-sample.bat

Each script runs mvn clean package, compiles the sample against the resulting JAR, and runs it — no manual classpath setup required.

Note: When running on JDK 21 or later you may see the following warning from Maven's own Guava dependency. It is cosmetic and can be safely ignored — it has no effect on the build or on the SDK at runtime:

WARNING: sun.misc.Unsafe::objectFieldOffset has been called by com.google.common.util.concurrent...

This will be resolved in a future Maven release.

Building the SDK

cd java
mvn clean package

Output: target/payflow.jar with zero external runtime dependencies. Copy it to your project's classpath.

Building with an IDE

Open the java/ directory as a Maven project in IntelliJ IDEA, Eclipse, or VS Code (Java Extension Pack). The IDE detects pom.xml and configures the source roots automatically.

Running the Samples Manually

The sample files live under src/paypal/payments/samples/. They are not included in payflow.jar; compile and run them separately:

# 1. Build the SDK
mvn clean package

# 2. Compile the sample into a local output directory
mkdir -p samplebin
javac -cp target/payflow.jar \
      -d samplebin \
      src/paypal/payments/samples/dataobjects/basictransactions/DOSaleComplete.java

# 3. Run (payflow.properties must be in the working directory)
java -cp "target/payflow.jar:samplebin" \
     paypal.payments.samples.dataobjects.basictransactions.DOSaleComplete

On Windows use ; instead of : as the classpath separator.

Note: payflow.properties must be present in the directory you run the java command from. The run-sample scripts automatically run from the java/ directory where the file lives.

API Documentation

The SDK ships with full Javadoc comments. Generate the HTML reference with:

# Windows (PowerShell)
.\generate-docs.ps1

# Linux / macOS / Git Bash
./generate-docs.sh

REM Windows (Command Prompt)
generate-docs.bat

Output is written to target/site/apidocs/index.html.

See also the Payflow Gateway Developer Guide.

Contributing

See CONTRIBUTING.md. PRs are welcome; open an issue first for major changes.

Older Versions

The last v4 SDK binaries are in the SDK Binaries directory.

License

SDK LICENSE