gremlin-driver/src/main/java/examples/BasicGremlin.java

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to you under the Apache License, Version 2.0 (the
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package examples;

import org.apache.tinkerpop.gremlin.driver.Cluster;
import org.apache.tinkerpop.gremlin.driver.remote.DriverRemoteConnection;
import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource;
import org.apache.tinkerpop.gremlin.structure.Vertex;

import java.util.List;

import static org.apache.tinkerpop.gremlin.process.traversal.AnonymousTraversalSource.traversal;

public class BasicGremlin {
    static final String SERVER_HOST = System.getenv().getOrDefault("GREMLIN_SERVER_HOST", "localhost");
    static final int SERVER_PORT = Integer.parseInt(System.getenv().getOrDefault("GREMLIN_SERVER_PORT", "8182"));
    static final String VERTEX_LABEL = System.getenv().getOrDefault("VERTEX_LABEL", "person");

    public static void main(String[] args) throws Exception {
        Cluster cluster = Cluster.build(SERVER_HOST).port(SERVER_PORT).create();
        GraphTraversalSource g = traversal().withRemote(DriverRemoteConnection.using(cluster, "g"));

        // Basic Gremlin: adding and retrieving data
        Vertex v1 = g.addV(VERTEX_LABEL).property("name","marko").next();
        Vertex v2 = g.addV(VERTEX_LABEL).property("name","stephen").next();
        Vertex v3 = g.addV(VERTEX_LABEL).property("name","vadas").next();

        // Be sure to use a terminating step like next() or iterate() so that the traversal "executes"
        // Iterate() does not return any data and is used to just generate side-effects (i.e. write data to the database)
        g.V(v1).addE("knows").to(v2).property("weight",0.75).iterate();
        g.V(v1).addE("knows").to(v3).property("weight",0.75).iterate();

        // Retrieve the data from the "marko" vertex
        Object marko = g.V().has(VERTEX_LABEL,"name","marko").values("name").next();
        System.out.println("name: " + marko);

        // Find the "marko" vertex and then traverse to the people he "knows" and return their data
        List<Object> peopleMarkoKnows = g.V().has(VERTEX_LABEL,"name","marko").out("knows").values("name").toList();
        for (Object person : peopleMarkoKnows) {
            System.out.println("marko knows " + person);
        }

        // Cleanup
        cluster.close();
        g.close();
    }
}