Using Infinispan with Kotlin

What You Will Learn

How to use the Infinispan Hot Rod Java client from Kotlin, including basic cache operations and Protobuf serialization with @Proto annotations on Kotlin data classes.

Prerequisites

Java 17+
An Infinispan Server running on localhost:11222 (or Docker/Podman available for Testcontainers)

Step 1: Add Kotlin and Infinispan Dependencies

Add the Kotlin standard library, Infinispan Hot Rod client, and Protostream dependencies to your pom.xml:

<dependency>
   <groupId>org.jetbrains.kotlin</groupId>
   <artifactId>kotlin-stdlib</artifactId>
   <version>${kotlin.version}</version>
</dependency>
<dependency>
   <groupId>org.infinispan</groupId>
   <artifactId>infinispan-client-hotrod</artifactId>
</dependency>
<dependency>
   <groupId>org.infinispan.protostream</groupId>
   <artifactId>protostream-processor</artifactId>
   <version>${version.protostream}</version>
</dependency>

Configure the Kotlin Maven plugin with kapt for annotation processing. See the pom.xml for the full build configuration.

Step 2: Define a Protobuf Entity in Kotlin

Use @Proto on a Kotlin data class. Fields must use @JvmField for Protostream compatibility:

@Proto
data class GreetingKotlin(@JvmField var name: String?=null,
                          @JvmField var greeting: String?=null)

@ProtoSchema(includeClasses = [GreetingKotlin::class])
interface GreetingSchemaKotlin : GeneratedSchema

Step 3: Connect and Perform Cache Operations

Use the same TutorialsConnectorHelper from Kotlin:

object InfinispanKotlinExample {
    lateinit var cacheManager: RemoteCacheManager
    lateinit var cache: RemoteCache<String, String>

    @JvmStatic
    fun main(args: Array<String>) {
        connectToInfinispan()
        manipulateCache()
        disconnect()
    }

    fun manipulateCache() {
        // Store a value
        cache.put("key", "value")
        // Retrieve the value and print it out
        println("key = ${cache["key"]}")
    }

    fun connectToInfinispan() {
        // Connect to the server
        cacheManager = TutorialsConnectorHelper.connect()
        // Obtain the remote cache
        cache = cacheManager.getCache(TUTORIAL_CACHE_NAME)
    }

    fun disconnect() {
        // Stop the cache manager and release all resources
        TutorialsConnectorHelper.stop(cacheManager)
    }
}

Step 4: Run the Tutorial

mvn package exec:java

You should see output like:

key = value

What’s Next

Get started with basic Java cache operations
Query your data with Ickle queries