package com.tinkerpop.blueprints.util;
import com.tinkerpop.blueprints.Direction;
import com.tinkerpop.blueprints.Edge;
import com.tinkerpop.blueprints.Graph;
import com.tinkerpop.blueprints.Vertex;
/**
* @author Marko A. Rodriguez (http://markorodriguez.com)
*/
public class GraphHelper {
/**
* Add a vertex to the graph with specified id and provided properties.
*
* @param graph the graph to create a vertex in
* @param id the id of the vertex to create
* @param properties the properties of the vertex to add (must be String,Object,String,Object,...)
* @return the vertex created in the graph with the provided properties set
*/
public static Vertex addVertex(final Graph graph, final Object id, final Object... properties) {
if ((properties.length % 2) != 0)
throw new RuntimeException("There must be an equal number of keys and values");
final Vertex vertex = graph.addVertex(id);
for (int i = 0; i < properties.length; i = i + 2) {
vertex.setProperty((String) properties[i], properties[i + 1]);
}
return vertex;
}
/**
* Add an edge to the graph with specified id and provided properties.
*
* @param graph the graph to create the edge in
* @param id the id of the edge to create
* @param outVertex the outgoing/tail vertex of the edge
* @param inVertex the incoming/head vertex of the edge
* @param label the label of the edge
* @param properties the properties of the edge to add (must be String,Object,String,Object,...)
* @return the edge created in the graph with the provided properties set
*/
public static Edge addEdge(final Graph graph, final Object id, final Vertex outVertex, final Vertex inVertex, final String label, final Object... properties) {
if ((properties.length % 2) != 0)
throw new RuntimeException("There must be an equal number of keys and values");
final Edge edge = graph.addEdge(id, outVertex, inVertex, label);
for (int i = 0; i < properties.length; i = i + 2) {
edge.setProperty((String) properties[i], properties[i + 1]);
}
return edge;
}
/**
* Copy the vertex/edges of one graph over to another graph.
* The id of the elements in the from graph are attempted to be used in the to graph.
* This method only works for graphs where the user can control the element ids.
*
* @param from the graph to copy from
* @param to the graph to copy to
*/
public static void copyGraph(final Graph from, final Graph to) {
for (final Vertex fromVertex : from.getVertices()) {
final Vertex toVertex = to.addVertex(fromVertex.getId());
ElementHelper.copyProperties(fromVertex, toVertex);
}
for (final Edge fromEdge : from.getEdges()) {
final Vertex outVertex = to.getVertex(fromEdge.getVertex(Direction.OUT).getId());
final Vertex inVertex = to.getVertex(fromEdge.getVertex(Direction.IN).getId());
final Edge toEdge = to.addEdge(fromEdge.getId(), outVertex, inVertex, fromEdge.getLabel());
ElementHelper.copyProperties(fromEdge, toEdge);
}
}
}