Install¶

Requirements¶

• JDK 11+ (Flink 1.20) or JDK 17+ (Flink 2.1)
• Maven 3.6+
• Apache Flink 1.20 / 2.1

The connector ships one artifact per supported Flink minor version:

Dependencies¶

The connector depends on org.lance:lance-core (7.0.0), lance-namespace (0.7.5) and Apache Arrow (18.3.0). These are pulled in transitively; you only need to add the connector artifact for your Flink version.

Lance's Java bindings ship a platform-specific JNI native library (liblance_jni.so / liblance_jni.dylib) inside the lance-core jar. Ensure you run on a supported platform (linux-x86-64, linux-aarch64, darwin-aarch64).

Maven¶

<!-- Flink 1.20 -->
<dependency>
    <groupId>org.apache.flink</groupId>
    <artifactId>lance-flink-1.20</artifactId>
    <version>0.2.0</version>
</dependency>

<!-- Flink 2.1 -->
<dependency>
    <groupId>org.apache.flink</groupId>
    <artifactId>lance-flink-2.1</artifactId>
    <version>0.2.0</version>
</dependency>

Build from source¶

# Both modules (requires JDK 17+, since the Flink 2.1 module targets Java 17)
mvn clean package

# A single module
mvn -pl lance-flink-1.20 test
mvn -pl lance-flink-2.1 test

The build produces a fat jar per module (e.g. lance-flink-2.1/target/lance-flink-2.1-*.jar). Add the jar to your Flink cluster or job classpath, then use the lance / lance-namespace catalog types in SQL.

Note on Arrow and Netty¶

The Arrow allocator defaults are set at runtime; if you see classloader-related SPI issues in tests, set the system property arrow.memory.allocator.type=Netty.

On JDK 17+, Arrow reaches java.nio.Buffer.address reflectively, so add --add-opens=java.base/java.nio=ALL-UNNAMED to the JVM arguments (the Maven build already does this through argLine).