    01: import java.awt.*;
    02: import java.util.*;
    03:
    04: /**
    05:    A simple graph with round nodes and straight edges.
    06: */
    07: public class SimpleGraph extends Graph
    08: {
    09:    public Node[] getNodePrototypes()
    10:    {
    11:       Node[] nodeTypes =
    12:          {
    13:             new CircleNode(Color.BLACK),
    14:             new CircleNode(Color.WHITE)
    15:          };
    16:       return nodeTypes;
    17:    }
    18:
    19:    public Edge[] getEdgePrototypes()
    20:    {
    21:       Edge[] edgeTypes =
    22:          {
    23:             new LineEdge()
    24:          };
    25:       return edgeTypes;
    26:    }
    27: }
    28:
    29:
    30:
    31:
    32: