gistfile1.java

package com.tinkerpop.blueprints.extension;

import com.tinkerpop.blueprints.Graph;
import com.tinkerpop.blueprints.Vertex;
import com.tinkerpop.blueprints.util.ElementHelper;

import java.util.Arrays;
import java.util.Optional;

/**
 * @author Marko A. Rodriguez (http://markorodriguez.com)
 */
public class IdExtension implements Extension {

    private final Extension.VertexExtension vertexExtension;
    private final Extension.GraphQueryExtension graphQueryExtension;
    private final String idKey;

    public IdExtension(final String idKey) {
        this.vertexExtension = new VertexExtension();
        this.graphQueryExtension = new GraphQueryExtension();
        this.idKey = idKey;
    }

    public Optional<Extension.VertexExtension> vertex() {
        return Optional.of(this.vertexExtension);
    }

    public Optional<Extension.GraphQueryExtension> graphQuery() {
        return Optional.of(this.graphQueryExtension);
    }

    public class GraphExtension implements Extension.GraphExtension {
        public Object[] beforeAddVertex(Graph graph, Object... keyValues) {
            Object[] newKeyValues = Arrays.copyOf(keyValues, keyValues.length + 2);
            newKeyValues[keyValues.length] = idKey;
            newKeyValues[keyValues.length + 1] = ElementHelper.getIdValue(keyValues);
            return newKeyValues;
        }
    }

    public class GraphQueryExtension implements Extension.GraphQueryExtension {


    }

    public class VertexExtension implements Extension.VertexExtension {

        public Object getId(Vertex vertex) {
            return vertex.getProperty(idKey);
        }

    }
}