GraphApplication.java

package ac.simons.neo4j.twitch;

import java.io.IOException;
import java.nio.file.Files;
import java.util.List;
import java.util.Map;

import org.neo4j.configuration.connectors.BoltConnector;
import org.neo4j.configuration.helpers.SocketAddress;
import org.neo4j.dbms.api.DatabaseManagementServiceBuilder;
import org.neo4j.driver.AuthTokens;
import org.neo4j.driver.GraphDatabase;
import org.neo4j.driver.Transaction;

public class GraphApplication {

	public static void main(String... a) throws IOException {

		// This is the db itself, should be long lived
		var graphDb = new DatabaseManagementServiceBuilder(Files.createTempDirectory("neo4j").toFile())
			.setConfig(BoltConnector.enabled, true)
			.setConfig(BoltConnector.listen_address, new SocketAddress("localhost", 7687))
			.build();

		// You could also use the graph database api and skip using bolt.
		// The advante of using build also in an embedded scenario: You can switch to a server with ease.
		// Same goes for the driver with the connection pool
		// The session itself is short lived
		try (
			var driver = GraphDatabase.driver("bolt://localhost:7687", AuthTokens.none());
			var session = driver.session()
		) {
			session.writeTransaction(t -> t.run("CREATE (p:Person {name: 'Arnold Schwarzenegger'}) - [:ACTED_IN] -> (:Movie {title: 'The Terminator'})").consume().counters().nodesCreated());


			var movies = session.readTransaction(GraphApplication::findMovieAndTheirActors);
			movies.forEach(System.out::println);
		}

		graphDb.shutdown();
	}

	record Person(String name) {
	}

	record Movie(String title, List<Person>actedIn) {
	}

	static List<Movie> findMovieAndTheirActors(Transaction tx) {

		var query = """
			MATCH (m:Movie) <- [:ACTED_IN] - (p:Person)
			WHERE m.title =~ $movieTitle
			RETURN m.title AS title, collect(p.name) AS actors
			""";

		return tx.run(query, Map.of("movieTitle", ".*The.*")).list(r -> {

			var actors = r.get("actors").asList(v -> new Person(v.asString()));
			var movie = new Movie(r.get("title").asString(), actors);
			return movie;
		});
	}
}

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
		 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>ac.simons.neo4j</groupId>
	<artifactId>neo4jtwitch</artifactId>
	<version>1.0-SNAPSHOT</version>

	<properties>
		<maven.compiler.source>14</maven.compiler.source>
		<maven.compiler.target>14</maven.compiler.target>

		<neo4j.version>4.0.1</neo4j.version>
		<neo4j-java-driver.version>4.0.1</neo4j-java-driver.version>
	</properties>

	<dependencies>
		<!-- Embbeded instance -->
		<dependency>
			<groupId>org.neo4j</groupId>
			<artifactId>neo4j</artifactId>
			<version>${neo4j.version}</version>
		</dependency>
		<dependency>
			<groupId>org.neo4j</groupId>
			<artifactId>neo4j-bolt</artifactId>
			<version>${neo4j.version}</version>
		</dependency>

		<!-- Driver (for connection) -->
		<dependency>
			<groupId>org.neo4j.driver</groupId>
			<artifactId>neo4j-java-driver</artifactId>
			<version>${neo4j-java-driver.version}</version>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>3.8.1</version>
				<configuration>
					<compilerArgs>--enable-preview</compilerArgs>
				</configuration>
			</plugin>
		</plugins>
	</build>

</project>