Minimal Kotlin/Gradle Example for Neo4j OGM

Application.kt

package so

import org.neo4j.ogm.annotation.GeneratedValue
import org.neo4j.ogm.annotation.Id
import org.neo4j.ogm.annotation.NodeEntity
import org.neo4j.ogm.annotation.Relationship
import org.neo4j.ogm.config.Configuration
import org.neo4j.ogm.session.SessionFactory

@NodeEntity
class Actor(var name: String) {

    @Id
    @GeneratedValue
    var id: Long? = null

    @Relationship(type = "ACTS_IN", direction = "OUTGOING")
    var movies = mutableSetOf<Movie>()

    fun actsIn(movie: Movie) {
        movies.add(movie)
        movie.actors.add(this)
    }
}

@NodeEntity
class Movie(var title: String, var released: Int) {

    @Id
    @GeneratedValue
    var id: Long? = null
    @Relationship(type = "ACTS_IN", direction = "INCOMING")
    var actors = mutableSetOf<Actor>()
}

object Neo4j {
    val configuration = Configuration.Builder()
            .uri("bolt://localhost")
            .credentials("neo4j", "test")
            .build()

    val sessionFactory = SessionFactory(configuration, "so")

    fun save() {

        val session = sessionFactory.openSession()

        val develsAdvocate = Movie("The Devil’s Advocate", 1997)
        var theMatrix = Movie("The Matrix", 1999)

        Actor("Carrie-Anne Moss").actsIn(theMatrix)

        val keanu = Actor("Keanu Reeves")
        keanu.actsIn(theMatrix)
        keanu.actsIn(develsAdvocate)

        session.save(develsAdvocate)
        session.save(theMatrix)

        session.clear()

        val theMatrixReloaded = session.load(Movie::class.java, theMatrix.id, 2)
        println("Found ${theMatrixReloaded.title}")
        for (actor in theMatrixReloaded.actors) {
            println("Actor ${actor.name} acted in ${actor.movies.joinToString { it.title }}")
        }

        sessionFactory.driver.close()
    }
}

fun main(args: Array<String>) {
    val neoInstance = Neo4j

    neoInstance.save()
}

build.gradle

buildscript {
    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-noarg:1.2.51"
    }
}

plugins {
    id 'org.jetbrains.kotlin.jvm' version '1.2.51'
}

apply plugin: 'kotlin'
apply plugin: "kotlin-noarg"

group 'soquestions'
version '1.0-SNAPSHOT'

repositories {
    mavenCentral()
}

dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib-jdk8"

    compile 'org.neo4j:neo4j-ogm-core:3.1.2'
    compile 'org.neo4j:neo4j-ogm-bolt-driver:3.1.2'

    compile 'org.slf4j:slf4j-simple:1.7.25'
}

noArg {
    annotation("org.neo4j.ogm.annotation.NodeEntity")
    annotation("org.neo4j.ogm.annotation.RelationshipEntity")
}

compileKotlin {
    kotlinOptions.jvmTarget = "1.8"
}
compileTestKotlin {
    kotlinOptions.jvmTarget = "1.8"
}