gremlin-examples/gremlin-java/BasicGremlin.java

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package examples;

import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource;
import org.apache.tinkerpop.gremlin.structure.Graph;
import org.apache.tinkerpop.gremlin.structure.Vertex;
import org.apache.tinkerpop.gremlin.tinkergraph.structure.TinkerGraph;

import java.util.List;

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

public class BasicGremlin {
    public static void main(String[] args) {
        Graph graph = TinkerGraph.open();
        GraphTraversalSource g = traversal().withEmbedded(graph);

        // Basic Gremlin: adding and retrieving data
        Vertex v1 = g.addV("person").property("name","marko").next();
        Vertex v2 = g.addV("person").property("name","stephen").next();
        Vertex v3 = g.addV("person").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("person","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("person","name","marko").out("knows").values("name").toList();
        for (Object person : peopleMarkoKnows) {
            System.out.println("marko knows " + person);
        }
    }
}